<p>The Energy Statistics Yearbook 2009 is a comprehensive collection of international energy statistics prepared by the United Nations Statistics Division. It is the fifty-third in a series of annual compilations which commenced under the title World Energy Supplies in Selected Years, 1929-1950. The principal objective of the Yearbook is to provide a global framework of comparable data on long-term trends in the supply of mainly commercial primary and secondary forms of energy. Data for each type of fuel and aggregated data for the total mix of commercial fuels are shown for individual countries and areas and are summarized into regional and world totals. This issue of the Yearbook contains data in original and common units (coal equivalent, oil equivalent, and joules) for the years 2006-2009.<br></p>