CENSUS 2000 UPDATE Indiana Counties
| Allen County | 1990 Census | 2000 Census | Percent Change | Number Change |
| Aboite Twp | 18,490 | 28,338 | 53.3% | 9,848 |
| Adams Twp | 30,962 | 31,394 | 1.4% | 432 |
| Cedar Creek Twp | 6,688 | 10,288 | 53.8% | 3,600 |
| Eel River Twp | 2,576 | 3,004 | 16.6% | 428 |
| Jackson Twp | 561 | 498 | -11.2% | (63) |
| Jefferson Twp | 1,882 | 1,958 | 4.0% | 76 |
| Lafayette Twp | 2,530 | 2,707 | 7.0% | 177 |
| Lake Twp | 1,914 | 1,985 | 3.7% | 71 |
| Madison Twp | 1,615 | 1,796 | 11.2% | 181 |
| Marion Twp | 3,529 | 3,655 | 3.6% | 126 |
| Maumee Twp | 2,459 | 2,619 | 6.5% | 160 |
| Milan Twp | 3,165 | 3,503 | 10.7% | 338 |
| Monroe Twp | 1,969 | 1,963 | -0.3% | (6) |
| Perry Twp | 10,909 | 18,170 | 66.6% | 7,261 |
| Pleasant Twp | 3,360 | 3,362 | 0.1% | 2 |
| St. Joseph Twp | 61,226 | 68,276 | 11.5% | 7,050 |
| Scipio Twp | 414 | 414 | 0.0% | - |
| Springfield Twp | 3,169 | 3,697 | 16.7% | 528 |
| Washington Twp | 27,416 | 33,105 | 20.8% | 5,689 |
| Wayne Twp | 116,005 | 111,117 | -4.2% | (4,888) |
| Allen Total | 300,836 | 331,849 | 10.3% | 31,013 |