Does the Species Protection Index for 198 Countries Converge Over Time?

Sustainable Development Goals adopted by The United Nations seek to protect and prevent the extinction of threatened species by 2020. Several countries even in the 1990s began expanding species protection to reach the 2020 goal early. This research investigates whether countries with low level of species protection efforts in the early years have been catching up faster in recent year. If so, how fast is the speed of catch-ups? We used a total of 198 countries during the period of 1990 to 2015. For the total as well as for the ten subgroups of countries, statistically valid catch-up effects have been discovered. However, speed of catch-up varies widely among the subgroups. Implications from these findings will be discussed.