| World population milestones in billions (USCB estimates) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Population | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| Year | 1804 | 1927 | 1959 | 1974 | 1987 | 1999 | 2012 | 2026 | 2042 |
| Years elapsed | –– | 123 | 32 | 15 | 13 | 12 | 13 | 14 | 16 |
| Population (in billions) |
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Year | 1804 | 1927 | 1959 | 1974 | 1987 | 1999 | 2012 | 2026 | 2042 | |||||||||
| Years elapsed | –– | 123 | 32 | 15 | 13 | 12 | 13 | 14 | 16 | |||||||||