摘要：The aim of the article is to study safety and sustainability of differentiation of performance of internal regions (NUTS 3) in the EU countries measured by the Sub-national Human Development Index (SHDI). The authors examine differentiation of the SHDI of internal regions in the EU countries by means of correspondence of distribution of this indicator [SHDI] of regional performance to Gauss curve, as well as by analyzing the SHDI of internal regions in the EU countries with the help of the coefficient of variation. As follows from the research, the authors proved that differentiation of regional performance in the EU over the last three decades were not chaotic but they were subjected to certain regularities: the distribution of performance of internal regions is normal, with metropolitan areas almost always being leaders of regional performance; regional differences in the area that is now the EU were increasing during the collapse of the Eastern European Socialist Bloc in the early 1990s, and they were declining later, as the regions adapted to the new conditions. So, identified regularities in performance of internal regions (NUTS 3) in the EU countries – normal distribution and spatial convergence – have been considered by the authors as safe and sustainable for further development of the whole EU and its countries.
关键词：EU countries; internal regions; differentiation; normal distribution; spatial convergence
