Research Article |
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Corresponding author: Juan Gabriel Brida ( elbrida@gmail.com ) © 2025 Emiliano Alvarez, Juan Gabriel Brida, Gaston Cayssials, Verónica Segarra.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Alvarez E, Brida JG, Cayssials G, Segarra V (2025) An empirical exploration of population dynamics and economic performance. Population and Economics 9(3): 26-59. https://doi.org/10.3897/popecon.9.e127348
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The purpose of this study is to conduct a descriptive and exploratory analysis of the complex relationships between population dynamics and economic performance. The paper introduces a methodology that enables a model-free topological and hierarchical description of the interaction between economic growth and population. For the empirical analysis, time series data on GDP and population from 111 countries over the period 1961–2019 is used. Using the concept of regimes, we classify countries based on the regime changes they experience throughout the analysis period. This classification allows us to identify groups of countries exhibiting similar behavioral patterns and clearly distinguish between these groups. Once these internally homogeneous groups are obtained, we characterize them by considering additional variables identified in the literature as proximate determinants of growth. Finally, we repeat the exercise with 30-year time windows to examine the emergence and evolution of each group and assess the potential for convergence or divergence among them. The study finds that the relationships between population dynamics and economic performance are non-linear, with the sign, intensity, and direction changing over time. This highlights the need for periodic policy evaluation and revision.
time series analysis, Minimal Spanning Tree, Hierarchical Tree, population dynamics, economic performance
The study of the relationship between economic and population growth has a long-standing tradition in economics. Population has played a central role in the analysis of economic growth since Adam Smith’s assertion (
Although the global population growth rate has declined over the past 60 years, consistent with the stylized facts of demographic transition, this process has not been uniform across countries. Different economies have experienced or are experiencing this transition at various times and with differing levels of intensity. Population growth rates exceeding 3% in many countries coexist with others where population levels are stable or declining. The potential effects of both rapid and slow or no population growth on economic growth, as well as their magnitude and the mechanisms through which they operate, remain largely uncertain. The empirical literature on the relationship between economic growth and demographic change has primarily focused on testing for cointegration between the two variables and examining their causal relationships. To contextualize our research, we provide a brief overview of this literature below. The present study examines the hierarchical structure and dynamic relationships between economic and population growth for a group of countries using a non-parametric approach. This method’s main advantage is that it enables the analysis and comparison of the interplay between population growth and economic growth without relying on a predetermined model. The cluster analysis further allows for the grouping of countries based on the similarity of their dynamic behavior.
This study has several objectives. Firstly, it introduces a methodology that provides a model-free topological and hierarchical description of the interaction between economic growth and population – an approach not previously explored in the literature to our knowledge. Secondly, while we do not delve into the underlying mechanisms at play (such as causes, effects, or propagation mechanisms), the proposed methodology indirectly indicates dynamic interdependence in the trajectories of economic growth and population change among countries. Additionally, it provides evidence that challenges single-model approaches for explaining the interdependence between demographic change and economic growth. The findings support the understanding of this relationship as non-linear and potentially non-monotonic.
The paper is organized as follows. The second section provides a review of the empirical literature on the relationship between economic growth and demographic change. The third section details the data and describes the set of tools used for conducting an empirical analysis of comparative economic growth without the imposition of an a priori model. Here, we explain the methodology for constructing minimum spanning trees and hierarchical trees. We introduce the concept of regime analysis and symbolic time series, and we define a distance metric within this framework to assess the proximity between countries. These tools enable us to identify and analyze the global structure, taxonomy, and hierarchy within our sample of countries, which we explore in the fourth section. Finally, the fifth section presents our final conclusions.
The relationship between economic growth and population has long been a topic of debate among policymakers, economists, demographers, and social scientists. Empirical research has found evidence of both negative and positive relationships between population growth and GDP per capita growth, as well as cases of independent relationships. Each of these findings, although seemingly contradictory, is supported by theoretical arguments, adding to the controversy surrounding the issue.
A rapidly growing population can lead to fewer resources per person, reduced physical capital per worker, and a higher proportion of dependents, placing greater demands on social protection infrastructure and resulting in lower economic growth. The neoclassical growth model (Solow, 1956) aligns with these views, linking economic growth to the population growth rate. The model predicts a negative relationship between population growth rate and per capita income: in the long run, higher population growth leads to lower steady-state per capita output. In the short term, an increase in the population growth rate results in reduced per capita output growth during the transition to a new equilibrium. This model does not distinguish between population and the labor force, implicitly assuming they grow at the same rate or that the population structure remains stable. Consequently, under this model, decreasing marginal returns lead to stable per capita output, and sustained economic growth can only occur through continuous technological progress.
In contrast, some endogenous growth models (
Other theoretical approaches build on the classical perspective of treating population as an endogenously determined variable. Researchers such as
In the empirical literature on the relationship between economic growth and demographic change, there is significant emphasis on testing for cointegration between the two variables and examining their causal relationships. The earliest empirical efforts to assess the impact of population change on economic growth involved correlation analysis. For instance,
From the late 1960s, many empirical studies employed cross-sectional analysis, often using “Barro regressions.” Studies by
The publication of the Penn Tables by the Maddison Project, particularly
By the late 1980s, the first studies employing cointegration and Granger causality analysis (
A significant number of studies have focused on individual countries, particularly developing nations with large populations, where concerns about the potential negative impact of population changes on income growth are prevalent.
India has also been the subject of various studies, including those by
Another common approach in academic literature is to consider regions by pooling sets of developing countries based on their geographic location. The findings in this area are varied.
A recent body of research (
The study found no evidence of Granger causality between population and economic growth in Belgium, Denmark, the Netherlands, the UK, the US, and New Zealand. Notably, causality directions were not static; when the analysis period was split into two sub-periods (1871–1951 and 1952–2013), many countries displayed changes in causality direction over time.
As Table
| Author | Period | Sample | Estimation Method | Findings |
|---|---|---|---|---|
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1950–1980 | 44 countries | Granger Causality test | p ⇒ + y |
| p ⇒ − y | ||||
| y ⇒ + p | ||||
| y ⇒ − p | ||||
| Non causality | ||||
| Kelley and Schmidt, (1995) | 1960–1970 | 86 countries | FEM, REM | Non impact p to y |
| 1970–1980 | ||||
| 1980–1990 | ||||
|
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1961–1991 | Nepal | Granger Causality test | p ⇒ + y |
| 1961–1990 | India | p + ⇔ − ** y | ||
| 1953–1989 | China | p – ⇔ + ** y | ||
| 1951–1990 | Ghana | y ⇒ − p | ||
| 1953–1989 | Sri Lanka | y ⇒ − p | ||
| 1961–1991 | Bolivia | Non Causality | ||
| 1949–1991 | Philippines | Non Causality | ||
| 1952–1991 | Guatemala | p ⇒ + ** y | ||
| 1961–1990 | Syria | y ⇒ − p | ||
| 1961–1990 | Peru | y ⇒ − * p | ||
| 1951–1990 | Thailand | Non Causality | ||
| 1958–1990 | Turkey | p – ⇔ + ** y | ||
| 1961–1990 | Chile | p – ⇔ + ** y | ||
| 1952–1990 | Argentina | Non causality | ||
| 1948–1986 | Mexico | p ⇒ + ** y | ||
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1960–1990 | Bangladesh | VAR | y ⇒ + p |
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1950–1993 | India | Cointegration (Johansen) | Non Causality |
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1950–1996 | 20 countries | Cointegration, VEC | p ⇒ + * y |
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1965–1990 | 70 countries | OLS | p ⇒ y |
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1900–1994 | Argentina, Brazil | Granger Test, VAR | Non Causality |
| 1925–1994 | Chile, Venezuela | |||
| 1921–1994 | Colombia | |||
| 1913–1994 | Mexico, Peru | |||
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1978–1998 | China | VI – GMM | p ⇒ − y |
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1950–2000 | Ivory Coast, Ghana, Kenya, Nigeria, South Africa, Sudan | VEC | p ⇔ − y |
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1973–1997 | Bangladesh | Cointegration, VEC | y ⇔ − p |
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1950–2000 | Japon, Korea, Thailand | Cointegration (Johansen), VAR | p ⇔ y |
| China, Singapore, Philippines | p ⇒ y | |||
| Honk Kong, Malaysia | y ⇒ p | |||
| Taiwan, Indonesia | Non Causality | |||
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1960–2000 | 25 OCDE countries | Cross-country regression, kernel non parametric | relationship, U-inverted |
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1950–2000 | 125 countries | OLS, (logy) (logy)2 | Africa – Asia. U-inverted. Europe: y ⇒ − p |
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1954–2005 | Taiwan | Cointegration (Johansen), VAR, Toda – Yamamoto | until 2000 p ⇒ + y, until 2005 insignificant |
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1978–1998 | China | VI – GMM | p ⇒ (−) y |
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1989–2007 | Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, Uzbekistan | ARDL | p ⇔ + y |
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1960–2000 | 110 countries | GAM non parametric | |
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1961–2003 | Thailand | Cointegration (Johansen), VEC | p ⇒ y |
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1960–2007 | Singapore | Cointegration (Johansen), VEC | y ⇔ + p |
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1952–1998 | China | VAR VEC | y ⇒ − p |
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1961–2003 | OLS | Effect positive (growth differential pop of working age – total pop) | |
| China | 46% | |||
| India | 39% | |||
| Pakistan | 25% | |||
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1960–2009 | Malaysia | Cointegration (Johansen), VAR, Toda – Yamamoto | Non Causality |
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1952–2007 | China | Cointegration, VECM | p ⇒ − y |
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1980–2007 | Panel 90 countries | simultaneous ADL | p ⇒ − y |
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1960–2007 | Indonesia | Cointegration non lineal, Breitung | A long-term equilibrium relationship exists |
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1980–2013 | India | Cointegration (Johansen), VEC | y ⇒ + p |
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1980–2013 | India | Cointegration (Johansen), VEC | p ⇒ + * y |
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1980–2010 | Nigeria | Cointegration (Johansen), VEC | p ⇔ y |
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1970–2010 | India | Cointegration (Johansen), VEC | y ⇒ (+) p |
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1961–2014 | China | ARDL | p ⇔ y |
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1975–2008 | Pakistan | ARDL | p ⇒ + y |
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1962–2012 | Mexico | VEC | p ⇔ y |
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1990–2013 | 7 countries South East Asia | Panel Regression Model, Structural Equation Models | p ⇔ y |
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1960–2013 | 30 most populous countries | VEC | p ⇔ + y |
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1960–2011 | India, Japan, South Korea, Sri Lanka, Malaysia, Pakistan, Singapore, Bangladesh, China, Indonesia | VEC – IRF. Impulse Response | p ⇒ + y |
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1960–2013 | USA, UK, Canada, China, India, Brazil | Panel cointegration, VEC | p ⇒ + y |
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1990–2013 | India | ARIMA | p ⇒ y |
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1970–2014 | Nigeria | MCE – IRF | p ⇒ + y |
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1961–2014 | China | ARDL | p ⇔ y |
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1960–2010 | 21 countries UE | ARDL | p ⇔ y |
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1980–2015 | India, Pakistan, Bangladesh, Sri Lanka, Nepal | Panel Cointegration. VEC | Non causality |
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1990–2015 | 13 West African countries | ARDL. Panel Causality. Dimitrescu – Hurlin | p ⇒ − y |
| 1981–2015 | Nigeria | |||
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1970–2015 | Zambia | ADL Cointegration (Johansen) | p ⇔ y |
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1970–2014 | 21 OECD countries | Panel VAR | p ⇒ + y |
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1971–2015 | Egypt | Cointegration, VEC | p ⇒ + y |
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1970–2017 | 10 high income countries | Cointegration, VEC | p ⇒ − y |
| 10 upper middle income countries | p ⇒ − y | |||
| 10 middle-income countries | p ⇒ + y | |||
| 10 low income countries | p ⇒ + y | |||
|
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1980–2018 | 57 Islamic countries | Cointegration (Johansen), VEC | p ⇒ + y |
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1974–2013 | Rwanda | ARDL | Effect positive (p ⇒ y) |
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1996–2016 | 10 Middle East | OLS | positive effect |
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1987–2017 | Ghana | ARDL | p ⇒ − y |
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1980–2020 | India | ARDL | p ⇒ + y |
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1980–2020 | Ethiopia | ARDL | p ⇒ + y |
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1820–1938 | USA, UK | Toda – Yamamoto | p ⇒ + y |
| 1950–2016 | Germany | Sims Granger causality test | p ⇔ +y | |
| France, Italy | y ⇒ + p |
The regression analyses reviewed, particularly those including cointegration testing, tend to assume a linear model, partly because their underlying model (usually Solow’s model) posits a linear relationship. The goal of these studies is to test for the existence of a linear long-term relationship between population and per capita output growth rates. However, there is a smaller group of studies that address the dynamic interplay between demographic change and economic growth using non-parametric approaches, often finding evidence of non-linear causal relationships between the variables. This is the case, for example, with
Their results portray a dynamic relationship between these two variables that changes over time. Initially, demographic change has a positive effect on economic growth, but the magnitude of the effect decreases over time and turns negative toward the end of the period. In other words, the relationship between the variables follows an inverted U-shape. The authors explain this phenomenon as an artifact of the three stages of demographic transitions: 1) high fertility/high mortality, 2) high fertility/low mortality, and 3) low fertility/low mortality.
Another example of a non-parametric approach is
Most of the empirical literature reviewed consists of linear regression models coupled with Granger causality tests. The linearity assumption is rarely discussed, and Granger causality tests are often misinterpreted. This is particularly true with respect to the policy recommendations suggested by the analyses. The fact that the results of several empirical studies on the same country, using similar econometric techniques, differ so radically is an indication of a possible non-linear underlying cointegration relationship that cannot be captured by Granger causality analysis. If the sign of the causal relationship can change, policy recommendations may be incorrect. Granger causality analysis is useful for forecasting, but the conclusions that can be drawn about the causal mechanism are limited. The Granger test should be a starting point for a more in-depth analysis of the causal relationship between economic and population growth. The conclusions that can be drawn about the causal mechanism, beyond temporal precedence, and the possibilities for policy manipulation are constrained.
Many of the studies using panel data models fail to check for homogeneity in the effect of explanatory variables across different countries. Zooming out from the details, the overall picture that emerges suggests that a single model is inadequate to explain the dynamic relationships between demographic change and economic growth across all countries and/or over long periods. This observation forms the starting point of our work. We seek to explore a novel path within the empirical literature that examines the dynamic relations between demographic change and economic growth, without imposing constraints on the form of these relationships or assuming homogeneity in the effects across countries. More specifically, we investigate the possibility of multiple patterns in the dynamic relationships between these two variables coexisting at the same time.
With this goal in mind, we aim to identify groups of countries, each internally homogeneous in terms of the dynamic relations between demographic change and economic growth, and at the same time clearly distinct from other groups. In short, this exercise highlights the advantages of a non-parametric methodology over the econometric approach. Note also that the proposed methodology considers both variables together, by analyzing the regime dynamics – essentially the qualitative dynamics of the two variables that represent structural changes. This method, which groups countries based on the dynamics of both variables, is an example of clustering multidimensional time series. It is fundamentally different from statistical grouping criteria that rely solely on each of the two variables independently.
The problem we aim to analyze involves the dynamics of two variables (population and economic output), where each economy is represented by a two-dimensional time series. To compare these dynamics and identify homogeneous groups with similar patterns, we need to introduce an appropriate metric. Since the units of measurement for each variable differ, and we do not know the relationship between them, we encounter a problem akin to the “Cartesian axis travel speed” issue in physics (
Recently, an interdisciplinary literature analyzing catastrophic regime shifts has emerged (see
In the economic literature, the term “regime” is used to describe a distinct way of behavior in an economy, which can be qualitatively distinguished from other regimes. One regime is defined to differentiate it from another, and it is meaningful to think in terms of multiple regimes. Intuitively, an economic regime refers to a set of rules that govern the economy as a system and determine its qualitative behavior (whether static or dynamic). According to
In terms of modeling, we can define a regime indirectly by defining a regime shift, which occurs when there is a change in the nature of the equation representing the functional form of the model. Regime shifts are associated with qualitative changes in the dynamics produced by variations in the model that governs an economy. These changes are essentially discontinuities or jumps.
The term complex economic dynamics is used in the literature to distinguish economic models whose trajectories exhibit irregular fluctuations and phase shifts, where by phase shift we mean the possibility that different types of qualitative dynamic behavior can be exhibited in different regions of state space, and this means that the laws governing change in the model change.
R. Day introduced multiphase economic dynamics and regime shifts in economic models to formalize the concept that ‘quite different forces or relationships govern behavior in different states’ (
How can we detect and characterize different regimes in complex problems involving multiple regimes? Various heuristics can be applied to define these regimes. One approach involves observing the phenomenon and identifying qualitatively different behaviors. For instance, the behavior of an economy with respect to inflation varies notably between deflation, moderate inflation, high inflation, and hyperinflation. In mathematical models, regimes are often constructed using Markov partitions (
Once the regimes are defined, we have a division of the state space into regions, each of which has qualitatively different dynamics. This gives rise to a dual dynamic: one within each regime and the other of regime change. This regime changes dynamics (which somehow captures the complexity of the system under study) – since it is defined in a discrete domain (the set of regimes) – can be represented by coding and symbolic dynamics (
This study represents population and economic performance dynamics through the evolution of the population growth rate and per capita GDP level. Annual data for per capita GDP (adjusted by Purchasing Power Parity, base year 2017), population, and corresponding growth rates were obtained from the Penn World Table 10.0 (PWT), a standard source for comparative economic growth studies (
As shown in Figure
Economic performance and population growth over the period analyzed. Notes: on the vertical axis, on the left, the level of GDP per capita (million dollars, PPP, year 2011) and, on the right, the rate of population growth percentage, both at the median, for the sample of countries analyzed. Source: qwn calculations based on PWT 10.0.
In this section, we describe the methodology used to compare and analyze the behavior of countries based on variables related to economic performance and demographic change. Our approach establishes a taxonomy and hierarchical ordering of countries, enabling us to evaluate the similarity of their trajectories. We construct the taxonomy using a nearest neighbor clustering procedure, which classifies time series according to their proximity as defined by a distance function. For the joint analysis of demographic change and economic performance, we apply a metric specifically designed for symbolic sequences to capture relevant patterns.
The methodology involves the following steps: compute the distance matrix, build the Minimum Spanning Tree (MST), compute the subdominant ultrametric distance matrix, construct the Hierarchical Tree (HT), and apply a hierarchical clustering stopping rule to determine the number of clusters in the sample. We begin by constructing the distance matrix D, DN×N, where N is the number of countries and the dij element is the distance between country i and country j. Next, we use Kruskal’s algorithm (
The MST arranges countries based on the most significant connections between them. Any two countries in the MST are connected through one or more vertices, representing the minimum distance path between them.
The third step involves deriving the subdominant ultrametric distance matrix D * (
Once the value of d*ij is calculated for all country pairs, we have the necessary elements to build the hierarchical tree (HT).
The HT indicates how to group countries for a specified number of clusters. For example, if you wish to divide the countries into eight groups, the HT specifies the allocation of countries to each group. To identify the statistically optimal number of clusters, we use the pseudo−T2 criterion (
To describe the qualitative behavior of the joint evolution of income and demographic growth, we introduce the concept of a regime (
We define two conditions: one sets a threshold for yearly population growth, and the other sets a threshold for per capita GDP. The state space is partitioned using median values for each variable, resulting in a uniform division. Although we initially considered using mean values for this partitioning, the results were similar, and median values offer clearer interpretations. Figure
Data partition in state space for the set of 111 countries at the start (left: year 1961) and end (right: year 2020) of the analyzed period. Notes: the partition is determined by the thresholds of the medians (in red) of the population growth rate and the per capita GDP level. The graph includes the mean of both variables (in green) to show the skewed distribution of these variables. The point cloud is defined by all countries in 1961 in the left graph and in 2020 in the right graph. Source: own calculations based on PTW 10.0.
Each region corresponds to a unique relationship between demographic change and economic performance. Consequently, a country transitioning from one region to another indicates a structural shift in how population and per capita output are related (a regime switch). Our analysis emphasizes the dynamics of these regimes, focusing on the sequence of regime transitions that countries experience over the study period.
Given the skewness of the variables, we opt to partition the state space using medians. In our analysis, each regime is defined by partitioning the state space into four regions, delineated by the annual median of each variable. This results in four distinct regions, each representing a different relationship between demographic change and economic performance. By calculating the median of per capita income (My) and population growth rate (Mgp) for all countries, we obtain the following partition of the state space of each year
R 1 = {(gp,y) : gp ≥ Mgp, y ≤ My}. (1)
Region R1 is characterized by low GDP per capita levels (below the median) and high population growth (above the median), which could be associated with economies trapped in so-called “poverty traps,” such as Senegal or Kenya.
R 2 = {(gp,y) : gp ≥ Mgp, y ≥ My}. (2)
In Region 2, we observe a virtuous relationship between economic performance and population growth, with GDP per capita levels in the top 50% and a growing population. We refer to this regime as ‘demographic dividend capture,’ as seen in countries like Korea.
R 3 = {(gp,y) : gp ≤ Mgp, y ≥ My}. (3)
Regime 3 is characterized by a slowly growing population and GDP per capita levels above the median, typical of OECD countries.
R 4 = {(gp,y) : gp ≤ Mgp, y ≤ My}. (4)
Finally, Regime 4 corresponds to a poor economy with a slowly growing population. This regime represents an economy that has completed the demographic transition but failed to capture the ‘demographic dividend.’ An example of this would be a country such as Bangladesh.
As depicted in Figure
Dynamics of regimes in Spain, China, Fiji and Tunisia, in the period 1961-2019. Notes: each point of each graph represents a pair (gp,y) corresponding to each of the four countries in each year between 1961 and 2019. Source: own calculations based on PTW 10.0.
Framing the problem in terms of multiple regimes through which countries move over time grants us the flexibility to account for different sequences of dynamic relationships between population and economic performance. An important regime sequence to consider is R1 → R2 → R3, which reflects the stylized facts of the demographic transition theory. In this ideal sequence, countries successfully capture the demographic dividend.
Simultaneously, a sequence of transitions from R1 → R4 indicates an economy that has completed its demographic transition but has not captured the demographic dividend. Table
Percentage of time each country or economy spends in each regime during the period of analysis
| Country | R 1 | R 2 | R 3 | R 4 | Country | R 1 | R 2 | R 3 | R 4 | Country | R 1 | R 2 | R 3 | R 4 |
| ARG | 0 | 0 | 88 | 12 | GAB | 0 | 71 | 29 | 0 | MYS | 7 | 93 | 0 | 0 |
| AUS | 0 | 27 | 73 | 0 | GBR | 0 | 0 | 100 | 0 | NAM | 51 | 39 | 10 | 0 |
| AUT | 0 | 0 | 100 | 0 | GHA | 71 | 20 | 2 | 7 | NER | 83 | 0 | 0 | 17 |
| BDI | 69 | 0 | 0 | 31 | GIN | 61 | 0 | 8 | 31 | NGA | 97 | 3 | 0 | 0 |
| BEN | 97 | 0 | 0 | 3 | GMB | 100 | 0 | 0 | 0 | NIC | 29 | 44 | 0 | 27 |
| BFA | 66 | 0 | 0 | 34 | GNB | 63 | 0 | 0 | 37 | NOR | 0 | 0 | 100 | 0 |
| BGD | 54 | 0 | 0 | 46 | GNA | 31 | 37 | 0 | 32 | NPL | 47 | 0 | 0 | 53 |
| BOL | 75 | 0 | 0 | 25 | GRC | 0 | 0 | 100 | 0 | NZL | 0 | 3 | 97 | 0 |
| BRA | 12 | 25 | 63 | 0 | GTM | 90 | 0 | 0 | 10 | PAK | 100 | 0 | 0 | 0 |
| BRB | 0 | 0 | 100 | 0 | HKG | 0 | 27 | 73 | 0 | PAN | 0 | 92 | 8 | 0 |
| BWA | 27 | 51 | 5 | 17 | HND | 100 | 0 | 0 | 0 | PER | 47 | 20 | 0 | 33 |
| CAF | 59 | 0 | 0 | 41 | HTI | 53 | 0 | 0 | 47 | PHL | 100 | 0 | 0 | 0 |
| CAN | 0 | 0 | 100 | 0 | IDN | 27 | 0 | 0 | 73 | PRT | 0 | 0 | 100 | 0 |
| CHE | 0 | 3 | 97 | 0 | IRL | 0 | 17 | 83 | 0 | PRY | 92 | 3 | 0 | 5 |
| CHL | 0 | 10 | 90 | 0 | IRN | 29 | 34 | 31 | 7 | ROU | 2 | 0 | 76 | 22 |
| CHN | 19 | 0 | 12 | 69 | ISL | 0 | 7 | 93 | 0 | RWA | 85 | 0 | 0 | 15 |
| CIV | 100 | 0 | 0 | 0 | ISR | 0 | 80 | 20 | 0 | SEN | 97 | 3 | 0 | 0 |
| CMR | 83 | 0 | 0 | 17 | ITA | 0 | 0 | 100 | SGP | 0 | 53 | 47 | 0 | |
| COD | 97 | 0 | 0 | 3 | JAM | 0 | 3 | 36 | 61 | SLV | 25 | 0 | 0 | 75 |
| COG | 97 | 0 | 0 | 3 | JOR | 86 | 14 | 0 | 0 | SWE | 0 | 0 | 100 | 0 |
| COL | 0 | 41 | 59 | 0 | JPN | 0 | 0 | 100 | 0 | SYC | 0 | 29 | 71 | 0 |
| COM | 95 | 0 | 0 | 5 | KEN | 100 | 0 | 0 | 0 | TCD | 71 | 0 | 0 | 29 |
| CPV | 41 | 0 | 0 | 59 | KOR | 15 | 0 | 73 | 12 | TGO | 97 | 0 | 0 | 3 |
| CRI | 0 | 75 | 25 | 0 | LKA | 12 | 3 | 7 | 78 | THA | 31 | 0 | 51 | 19 |
| CYP | 0 | 20 | 80 | 0 | LSO | 51 | 0 | 0 | 49 | TTO | 0 | 3 | 97 | 0 |
| DEU | 0 | 0 | 100 | 0 | LUX | 0 | 24 | 76 | 0 | GTM | 42 | 58 | 0 | 0 |
| DNK | 0 | 0 | 100 | 0 | MAR | 41 | 0 | 0 | 59 | TUN | 17 | 24 | 31 | 29 |
| DOM | 24 | 10 | 61 | 5 | MDG | 86 | 0 | 0 | 14 | TUR | 0 | 44 | 56 | 0 |
| DZA | 7 | 71 | 22 | 0 | MEX | 0 | 46 | 54 | 0 | TWN | 3 | 15 | 82 | 0 |
| ECU | 44 | 56 | 0 | 0 | MLI | 51 | 0 | 0 | 49 | TZA | 97 | 0 | 0 | 3 |
| EGY | 85 | 1 | 0 | 14 | MLT | 0 | 0 | 86 | 14 | UGA | 100 | 0 | 0 | 0 |
| ESP | 0 | 8 | 92 | 0 | MOZ | 75 | 0 | 0 | 25 | URY | 0 | 0 | 100 | 0 |
| ETH | 73 | 0 | 0 | 27 | MRT | 78 | 5 | 10 | 7 | USA | 0 | 0 | 100 | 0 |
| FIN | 0 | 0 | 100 | 0 | MOZ | 75 | 0 | 0 | 25 | VEN | 0 | 86 | 3 | 10 |
| FJI | 10 | 10 | 46 | 34 | MRT | 78 | 5 | 10 | 7 | ZAF | 0 | 78 | 22 | 0 |
| FRA | 0 | 0 | 100 | 0 | MUS | 0 | 8 | 92 | 0 | ZMB | 88 | 12 | 0 | 0 |
| GAB | 0 | 71 | 29 | 0 | MWI | 90 | 0 | 0 | 10 | ZWE | 66 | 3 | 2 | 29 |
The first observation is the diversity of behaviors within the sample of countries, evident from the range of regimes they visit and the time spent in each. Some countries alternate between R3 and R4, never visiting R1 or R2, while others do the opposite, alternating between R1 and R2 and never entering R3 or R4. A third group of countries transitions through all four regimes. In short, the sample does not exhibit a single, uniform pattern but rather a multitude of distinct pathways.
However, this initial approach to understanding regime dynamics has a significant limitation: it overlooks the sequence in which countries transition between regimes, which is crucial for understanding regime dynamics comprehensively. Specifically, it fails to capture information on regime transitions. To address this limitation, we employ symbolic series to represent regime dynamics. This method reduces the information space of our problem while retaining essential details about regime transitions.
If we label each regime Ri by the symbol i, we can substitute the original bi-variate time series {(gp1,y1),(gp2,y2),...,(gpT,yT)} by a sequence of symbols {s1,s2,...,sT} such that st = j if and only if (gpt,yt) belongs to Rj. This Symbolic Series that summarizes the most relevant qualitative information on the dynamics of a country’s regime.
To group the 111 countries based on their different economic-demographic performance, we use the non-parametric approach described in the previous section. The steps include computing the distance matrix, building the MST, computing the subdominant ultrametric distance matrix, constructing the HT, and applying a hierarchical clustering stopping rule to determine the number of clusters in the sample.
As previously discussed, the joint analysis of demographic change and economic performance requires a metric different from the standard Euclidean distance. Since we are working with regime dynamics represented by symbolic sequences, it is necessary to measure the distances between these symbolic sequences.
To detect clusters of countries with similar regime dynamics, we use the discrete distance measure, a common approach for symbolic time series analysis. For any given pair of countries, we first compute the yearly distance by comparing their regime status. The distance is assigned a value of zero if both countries are in the same regime and a value of one if they are in different regimes. In the second step, we sum these yearly distances over the entire period to determine the total distance between the two countries.
Given two symbolic series and corresponding to countries i and j, we define the following distance:
(5)
where (6)
Intuitively, the more frequently two countries share the same regime, the smaller their distance will be. If two countries have identical sequences of regimes throughout the analysis period, they achieve the minimum possible distance, which is zero. Conversely, the maximum possible distance, denoted as T, occurs when two countries never share the same regime in any year.
To construct the MST, we employ Kruskal’s algorithm. The MST for this study, built with 111 nodes and 110 edges, emphasizes the most significant distances for each country. The graph provides an arrangement of countries that identifies the strongest connections within the sample. Each connection between two nodes represents the shortest path linking those countries, illustrating shared or differing regime dynamics.
Figure
Minimum Spanning Tree. The two clusters and the outliers are showed in the MST. Notes: each country is represented by a node in the MST. The first cluster is highlighted in green. See Appendix, Table
Node D (marked in orange) represents another cluster that includes Uganda (UGA), the Philippines (PHL), Pakistan (PAK), Kenya (KEN), Honduras (HND), Côte d’Ivoire (CIV), and Gambia (GMB). These countries predominantly shared the R1 regime during the analysis period.
Nodes highlighted in red indicate countries with distinct regime dynamics, differing from those in Nodes A and D.
Given a predetermined number of groups for dividing the sample, the HT indicates how countries should be grouped. For instance, if the goal is to partition the sample into eight groups, the HT can be used to identify which countries belong to each group. The final step involves applying a hierarchical clustering stopping rule to determine the optimal number of groups.
In hierarchical cluster analysis, the output is typically a hierarchical tree that begins by grouping individual cases. However, we often seek a specific cluster solution, meaning we want to cut the hierarchical tree at a particular level to obtain a single classification of cases into a fixed number of categories. In the cluster analysis conducted using a hierarchical classification method, two groups of countries are identified. The stopping rules employed are the Pseudo-F (
There are various methods to determine where to stop the clustering process. These methods often start with one cluster and then evaluate whether splitting it into two improves a measure of fit (such as a loss function), continuing this process for each subsequent solution. The Calinski-Harabasz pseudo-F index is one such measure. It compares the sum of squared distances within the partitions to that of the unpartitioned data, adjusting for the number of clusters and the number of cases (
Both tests indicate that the optimal number of clusters is two. These two well-differentiated clusters contain 103 of the 111 countries, or approximately 90% of the countries in the sample.
Cluster analysis stopping rules are used to determine the optimal number of clusters. A stopping-rule value is computed for each cluster solution at each level of the hierarchy. For both rules used in this analysis, larger values indicate more distinct clustering. In Figure
Hierarchical Tree. Notes: in the hierarchical tree, two clusters of homogeneous countries (1961-2020) are identified based on their population dynamics and economic performance. Table
The first cluster, referred to as mature economies, includes 51 countries and is the most homogeneous, with the smallest sum of group distances in the Minimum Spanning Tree (MST). This cluster comprises Argentina, Australia, Austria, Belgium, Brazil, Barbados, Canada, Switzerland, Chile, Colombia, Costa Rica, Cyprus, Germany, Denmark, the Dominican Republic, Algeria, Spain, Finland, France, Gabon, the United Kingdom, Greece, China, Hong Kong, Ireland, Iceland, Israel, Italy, Japan, the Republic of Korea, Luxembourg, Mexico, Malta, Mauritius, Malaysia, the Netherlands, Norway, New Zealand, Panama, Portugal, Romania, Singapore, Sweden, Seychelles, Thailand, Trinidad and Tobago, Turkey, Taiwan, Uruguay, the United States, Venezuela, and South Africa. These countries are currently classified as upper-income or upper-middle-income nations.
In terms of regime dynamics, the common feature in this group is that they do not visit the R1 and R4 regimes throughout the entire analysis period. Most countries in this group remain in the R3 regime for the majority of the time. Some countries experience a brief initial phase alternating between R1 and R2 (with R2 being dominant), lasting at most for the first decade and a half of the analysis period.
The second group, which we call young economies, contains 52 countries and is less homogeneous than the previous one. It includes Burundi, Benin, Burkina Faso, Bangladesh, Bolivia, Central African Republic, China, Côte d’Ivoire, Cameroon, Democratic Republic of the Congo, Republic of the Congo, Comoros, Cabo Verde, Ecuador, Egypt, Ethiopia, Ghana, Guinea, Gambia, Guinea-Bissau, Guatemala, Honduras, Haiti, Indonesia, India, Jordan, Kenya, Sri Lanka, Lesotho, Morocco, Madagascar, Mali, Mozambique, Mauritania, Malawi, Namibia, Niger, Nigeria, Nepal, Pakistan, Philippines, Paraguay, Rwanda, Senegal, Syrian Arab Republic, Chad, Togo, Tanzania, Uganda, Zambia, and Zimbabwe.
As with the previous cluster, the defining characteristic of the countries in this group is that, during the period of analysis, they alternate almost entirely between regimes R1 and R4, mirroring the dynamics of the mature economies cluster. The countries in this cluster do not visit the R3 regime and only briefly enter the R2 regime. These countries are mostly lower-middle-income or low-income, with high population growth. They are either still in the intermediate stages of demographic transition or have completed the transition but have not yet reaped the demographic dividend.
Table
| GDP | Population | ||||||||
| Mean | Median | Min | Max | Mean | Median | Min | Max | N | |
| Cluster 1 | 21.784 | 17.520 | 251 | 112.942 | 1.19% | 1.04% | -18.05% | 4.33% | 51 |
| Cluster 2 | 2.746 | 2.138 | 428 | 13.988 | 2.46% | 2.59% | -6.54% | 13.34% | 52 |
| All countries | 11.800 | 5.485 | 251 | 112.942 | 1.85% | 1.93% | -18.05% | 13.34% | 111 |
Cluster obtained: geographical location. Notes: cluster 1 is shown in green, Cluster 2 is shown in orange and the outliers are shown in red. Source: authors’ own elaboration.
As indicated in Table
The proposed methodology separates the dynamics of the two variables into two distinct forms: one within each regime and another associated with regime transitions. It is the latter dynamic, representing structural change, that is emphasized in this analysis. Therefore, the results suggest that we have two distinct groups, each homogeneous in terms of regime dynamics.
To conclude this section, we characterize the two groups based on a set of variables that the literature considers closely related to the two dimensions of our regime dynamics analysis. Specifically, these variables are interconnected within a dynamic system that reflects both dimensions of our study. First, we consider the Economic Complexity Index (ECI), which serves as an indicator of the knowledge embedded in a country’s productive structure (
Second, we include the Human Development Index (HDI), which reflects the living conditions of a population in terms of life expectancy, education, and income. Finally, we also consider a measure of human capital accumulation in each country.
Figure
Figure
Economic performance and population growth. Notes: evolution of the median for each variable by cluster and for the entire sample. Source: authors’ own elaboration.
As shown in Figures
Economic Complexity Index. Notes: we use freely available data on the Economic Complexity Index from the MIT Economic Complexity Observatory. Source: authors’ own elaboration. Available on: http://atlas.media.mit.edu.
Human Development Index. Notes: Human Development Index evolution (average) per group. Source: UN (2020). Human Development Index (HDI) and authors’ own elaboration. Available on: http://hdr.undp.org/en/indicators/137506
Human Capital Index. Notes: Human Capital per capita evolution (average) per group. Source: PWT 10.0, Human capital index, based on years of schooling and returns to education and authors’ own elaboration.
In summary, we grouped countries based on their regime dynamics as represented by symbolic series constructed from population growth rates and per capita GDP. We found that these groups could be clearly differentiated using other variables not included in the symbolization but considered fundamental in the literature. This suggests that symbolizing just two variables significantly reduced the complexity of a dynamic system involving multiple variables, while still preserving valuable information that allowed us to characterize the entire system.
To complete this stage of the analysis, we repeated the exercise using the growth rates of population and GDP per capita, rather than their levels. This approach partitions the state space based on the median of both rates for each period. Applying the same clustering methodology, we found that the results were quite similar. In summary, the clusters are distinguished not only by their population growth and economic performance but also by their economic growth dynamics.
In the previous analysis, we gathered insights into the dynamics over the entire period. As noted earlier, the clusters exhibit distinctly different dynamics throughout the period, with notable qualitative differences between them. In this section, we examine the evolution of the clusters over time. Our aim is to investigate whether the size and composition of the clusters remained stable and, ultimately, to assess whether there was a trend toward convergence, meaning whether the clusters displayed increasingly similar dynamics or diverged further apart.
To conduct this analysis, we divided the period into 27 overlapping 30-year windows and repeated the previous clustering procedure for each window.
The results indicate that the number of clusters remained consistent with the earlier analysis. The composition of each cluster was relatively stable, with only a few countries changing clusters over time. For instance, Nicaragua, Ecuador, and Namibia were initially part of Cluster 1 in the first windows, shifted to Cluster 2 during the intermediate windows, and eventually moved out of both clusters.
In terms of homogeneity within each group, there is a clear trend toward increasingly similar trajectories among countries within the same group. As the analysis progresses across the different time windows, the sub-cluster of countries exhibiting identical dynamics grows in size.
To assess whether the countries in the sample, considered collectively, moved closer together or diverged over the period of analysis, a measure of global distance is necessary. Using the methodology outlined by
The evolution of this global distance across the trees for each time window is shown in Figure
Evolution of the diameter of the MST for windows of 30 years. Source: authors’ own elaboration.
The observed decreasing trend in the MST’s diameter does not indicate convergence between the clusters. Instead, it reflects the increasing compactness within each cluster, as the trajectories of countries within each group become more similar.
The relationship between economic and population growth has been a longstanding topic of study in economics. However, there is no theoretical consensus on the scope and mechanisms through which population growth and economic growth influence each other. Empirical evidence further complicates this issue, as findings from numerous studies remain contradictory and inconclusive. Given this diversity of outcomes reported in the literature, we opted for a descriptive and exploratory analysis to investigate the links between economic and population growth.
In our paper, we introduce a methodology that facilitates a model-free topological and hierarchical description of the relationship between economic growth and population dynamics. While we do not explore the underlying mechanisms at play, such as causes, effects, or propagation pathways, the proposed methodology indirectly points to the presence of dynamic interdependence in the trajectories of economic growth and population change across countries. Additionally, it provides evidence against single-model approaches for explaining the complex interdependence between demographic changes and economic growth.
By applying clustering techniques and introducing the concept of regime dynamics, we aim to identify groups of countries that are internally homogeneous in their dynamic relationships between demographic change and economic growth, while remaining clearly distinct from other groups.
Our findings reveal evidence of multiple coexisting patterns in the dynamic relations between these variables. Specifically, we identify two well-differentiated groups of countries, each displaying a unique dynamic pattern: mature economies and young economies.
The first group, consisting predominantly of OECD countries, is characterized by low population growth and strong economic performance. In contrast, the group of young economies, primarily located in Central Africa, exhibits above-average population growth paired with poor economic growth.
The methodology we use also allows for the inclusion of additional variables such as the Economic Complexity Index (ECI), the Human Development Index (HDI), and human capital accumulation. This has enabled us to identify key characteristics of the productive structure and living standards shared by countries within the same cluster. The analysis reveals clear differences between the clusters in terms of the evolution of these variables, which serves to reinforce the conclusions from the previous analysis.
When analyzing the overall dynamics of the countries in the sample, we observe a slight tendency for their trajectories to converge. However, this convergence is not due to a blending of dynamics between the clusters, but rather to increased homogeneity within each cluster. Over time, each cluster becomes more compact, and the trajectories of countries within the same cluster become increasingly similar.
Our findings – on the variety of ways in which population dynamics are linked to economic performance, and how these relationships evolve – have important implications for the design and evaluation of public policies. Given that the relationships between these variables are likely non-linear, and that their sign, intensity, and direction can change over time, it is crucial to periodically evaluate and revise policies to account for these dynamics.
Finally, we would like to highlight some limitations of the analysis and suggest directions for future research. One key limitation is that our analysis does not differentiate between natural population growth and the impact of net immigration. This distinction is important because the dynamic effects of these two sources of population change on economic output are likely to differ. Incorporating this distinction into future research is therefore a crucial next step.
Additionally, it is important to reiterate that this study is exploratory and descriptive in nature. As such, it does not allow for conclusions regarding causal relationships, nor does it provide insights into the sign or magnitude of any potential effects.
A promising direction for future research would be to conduct a cointegration and causality analysis using panel data, based on the groups identified in this study (countries with similar dynamics in terms of population growth and economic performance). This would involve testing for potential shifts in the relationship between population and economic growth at specific points in time. Prior to this, it would be essential to analyze the hypothesis of linearity and compare the results with those found in the existing empirical literature.
Emiliano Alvarez – member of economic dynamics research group, Department of Quantitative Methods, Faculty of Economics and Administration, University of the Republic. Montevideo, 11200, Uruguay. Email: emiliano.alvarez@fcea.edu.uy
Juan Gabriel Brida – member of economic dynamics research group, Department of Quantitative Methods, Faculty of Economics and Administration, University of the Republic. Montevideo, 11200, Uruguay. Email: elbrida@gmail.com
Gaston Cayssials – member of economic dynamics research group, Department of Quantitative Methods, Faculty of Economics and Administration, University of the Republic. Montevideo, 11200, Uruguay. Email: gacayssials@gmail.com
Verónica Segarra – member of economic dynamics research group, Department of Quantitative Methods, Faculty of Economics and Administration, University of the Republic. Montevideo, 11200, Uruguay. Email: verosegarras@gmail.com
| Code | Country | Code | Counry | Code | Country |
| ARG | Argentina | GAB | Gabon | NAM | Namibia |
| AUS | Australia | GBR | United Kingdom | NER | Niger |
| AUT | Austria | GHA | Ghana | NGA | Nigeria |
| BDI | Burundi | GIN | Guinea | NIC | Nicaragua |
| BEL | Belgium | GMB | Gambia | NLD | Netherlands |
| BEN | Benin | GNB | Guinea-Bissau | NOR | Norway |
| BFA | Burkina Faso | GNQ | Equatorial Guinea | NPL | Nepal |
| BGD | Bangladesh | GRC | Greece | NZL | New Zealand |
| BOL | Bolivia | GTM | Guatemala | PAK | Pakistan |
| BRA | Brazil | HKG | China, Hong Kong SAR | PAN | Panama |
| BRB | Barbados | HND | Honduras | PER | Peru |
| BWA | Botswana | HTI | Haiti | PHL | Philippines |
| CAF | Central African Republic | IDN | Indonesia | PRT | Portugal |
| CAN | Canada | IND | India | PRY | Paraguay |
| CHE | Switzerland | IRL | Ireland | ROU | Romania |
| CHL | Chile | IRN | Iran | RWA | Rwanda |
| CHN | China | ISL | Iceland | SEN | Senegal |
| CIV | Côte d’Ivoire | ISR | Israel | SGP | Singapore |
| CMR | Cameroon | ITA | Italy | SLV | El Salvador |
| COD | D.R. of the Congo | JAM | Jamaica | SWE | Sweden |
| COG | Congo | JOR | Jordan | SYC | Seychelles |
| COL | Colombia | JPN | Japan | SYR | Syrian Arab Republic |
| COM | Comoros | KEN | Kenya | TCD | Chad |
| CPV | Cabo Verde | KOR | Republic of Korea | TGO | Togo |
| CRI | Costa Rica | LKA | Sri Lanka | THA | Thailand |
| CYP | Cyprus | LSO | Lesotho | TTO | Trinidad and Tobago |
| DEU | Germany | LUX | Luxembourg | TUN | Tunisia |
| DNK | Denmark | MAR | Morocco | TUR | Turkey |
| DOM | Dominican Republic | MDG | Madagascar | TWN | Taiwan |
| DZA | Algeria | MEX | Mexico | TZA | Tanzania |
| ECU | Ecuador | MLI | Mali | UGA | Uganda |
| EGY | Egypt | MLT | Malta | URY | Uruguay |
| ESP | Spain | MOZ | Mozambique | USA | United States |
| ETH | Ethiopia | MRT | Mauritania | VEN | Venezuela |
| FIN | Finland | MUS | Mauritius | ZAF | South Africa |
| FJI | Fiji | MWI | Malawi | ZMB | Zambia |
| FRA | France | MYS | Malaysia | ZWE | Zimbabwe |