The Environmental Kuznets Curve Hypothesis: Results of the Last 30 Years

Abstract

According to the environmental Kuznets curve (EKC) hypothesis, the relationship between GDP per capita (plotted on the horizontal axis) and environmental degradation (plotted on the vertical axis) forms an inverted U-shaped curve when represented in a coordinate system. Despite nearly three decades having passed since its initial proposal, the research community has yet to reach consensus regarding both the precise nature of this relationship and a universally accepted measure of environmental degradation. This paper aims to systematically review the current state of understanding regarding the EKC hypothesis, including its principal criticisms. This review is particularly timely because the EKC hypothesis has the potential to elucidate the predominant determinants of a nation's environmental condition, thus playing a crucial role in formulating environmental policy frameworks.