World Population

Year

1800 - - - - - - 1,000,000,000

1900 - - - - - - 1,600,000,000

1960 - - - - - - 3,000,000,000

1973 - - - - - - 4,000,000,000

1987 - - - - - - 5,000,000,000

2000 - - - - - - 6,000,000,000

2016 - - - - - - 7,400,000,000

Today - - - http://www.worldometers.info/

See also my review of Mark Lynas' book Six Degrees