Notes: Except where indicated, regional groupings are based on United Nations geographical regions, with some modifications necessary to create, to the extent possible, homogeneous groups of countries for analysis and presentation.
注：除另有说明外，区域分组以联合国的地理区域为依据，并作了必要修改，以尽可能将同类国家分在一个组中，便于分析和编列。