population of world

The raw data is from the U.S. Census Bureau, and is not uncontroversial. For instance, the UN, with its data, considered 1999 October 12 to be the "day of six billion", but the approximation here (which I for one have more faith in) puts it at 1999 June 18 or 19 (depending on what time zone you're in), nearly four months earlier

2009 now check population