| Statistic | Demontigny | Trois-Rivières | Quebec |
| Population | 1,832 | 138,766 | 8,565,732 |
| Population density (sq km) | 401 | 478 | 6 |
| Median age | 49.3 | 46.6 | 42.6 |
| Male/Female ratio | 1.0:1 | 1.1:1 | 1.0:1 |
| Married couples | 48% | 43% | 50% |
| Families w/ kids at home | 31% | 34% | 40% |
| Speak English only | 0.2% | 0.2% | 4.7% |
| Speak French only | 68.9% | 68.3% | 49.5% |
| Data | Percent |
| Black | 1.0% |
| Latin American | 0.9% |
| Arab | 0.1% |
| Southeast Asian | 0.1% |
| N/A | 0.0% |
| Data | Percent |
| France | 0.3% |
| Cameroon | 0.3% |
| Philippines | 0.2% |
| Algeria | 0.1% |
| Colombia | 0.1% |