Decatur, IL Population by Decades
| Date |
Population |
Population
Change |
Annual
% Change |
| 1900 | 44,003 | - | - |
| 1910 | 54,186 | 10,183 | 2.1 |
| 1920 | 65,175 | 10,989 | 1.9 |
| 1930 | 81,731 | 16,556 | 2.3 |
| 1940 | 84,693 | 2,962 | 0.4 |
| 1950 | 98,853 | 14,160 | 1.6 |
| 1960 | 118,257 | 19,404 | 1.8 |
| 1970 | 125,010 | 6,753 | 0.6 |
| 1980 | 131,375 | 6,365 | 0.5 |
| 1990 | 117,206 | -14,169 | -1.1 |
| 2000 | 114,706 | -2,500 | -0.2 |
Source: U.S. Bureau of Census
|
