The FAO Production Yearbook is a compilation of statistical data on basic agricultural products for all countries and territories of the world. This yearbook includes data series on area, yield and production of crops; on livestock numbers and products; and on population, land use, irrigation and farm machinery, for the years 1999-2001. It also gives total and per caput index numbers that highlight trends in food and agricultural production across all countries and continents for the years 1991-2002. Statistical information is mainly based on data provided by countries through electronic media, questionnaires of the FAO Statistics Division or offical statistics publications. In the absence of official data, FAO makes estimates based on the best information available.