Six Billion of Us
Updated March 17, 2017 | Factmonster Staff 
According to the U.S. Census Bureau, the world population reached 6 billion on July 19, 1999, at about 12:24:02 AM GMT (July 18 at 8:24:02 PM EDT). The Census figure is an estimate and not meant to be an exact accounting of every birth and death throughout the world. Differing estimates exist. The United Nations celebrated the “Day of 6 Billion” three months later, on October 12, 1999.
World Population Milestones
- 1 billion in 1804
- 2 billion in 1927 (123 years later)
- 3 billion in 1960 ( 33 years later)
- 4 billion in 1974 ( 14 years later)
- 5 billion in 1987 ( 13 years later)
- 6 billion in 1999 ( 12 years later)
Source: United Nations Population Division
