This data collection, the first edition in the World Handbook series, comprises interval-level social, political, economic, and demographic indicators for 141 countries in the period 1961-1963. Information is provided for the size of the country, the number of years independent, total population, population per square kilometer, gross national product (GNP), gross capital formation as a percentage of the GNP, government revenue and expenditure, foreign trade, employment in industry and in agriculture, degree and annual increase of urbanization, and voting characteristics.