| PEOPLE | Walnut Creek | Irvine | United States |
| Population | 64,173 | 212,375 | 308,035,306 |
| Pop. Density | 3,248 | 3,213 | 87 |
| Pop. Change | 0.54% | 45.98% | 8.07% |
| Median Age | 47.9 | 33.9 | 37.3 |
| Households | 30,443 | 78,978 | 116,716,292 |
| Household Size | 2.1 | 2.6 | 2.58 |
| Male Population | 46.34% | 48.70% | 49.27% |
| Female Population | 53.66% | 51.30% | 50.96% |
| Married Population | 48.04% | 47.32% | 47.02% |
| Single Population | 51.96% | 52.68% | 52.98% |
| ESTIMATED TOTAL POPULATION BY AGE | | | |
| Age 0 to 4 | 4.10% | 5.65% | 6.56% |
| Age 5 to 9 | 4.57% | 6.00% | 6.61% |
| Age 10 to 14 | 4.86% | 6.05% | 6.71% |
| Age 15 to 17 | 3.17% | 3.81% | 4.21% |
| Age 18 to 20 | 1.48% | 4.72% | 2.95% |
| Age 21 to 24 | 4.13% | 9.59% | 7.01% |
| Age 25 to 34 | 11.82% | 15.80% | 13.33% |
| Age 35 to 44 | 11.77% | 15.59% | 13.33% |
| Age 45 to 49 | 14.08% | 14.05% | 14.61% |
| Age 50 to 54 | 14.08% | 14.05% | 14.61% |
| Age 55 to 59 | 13.43% | 10.05% | 11.84% |
| Age 60 to 64 | 13.43% | 10.05% | 11.84% |
| Age 65 to 74 | 10.47% | 5.11% | 7.05% |
| Age 75 to 84 | 9.51% | 2.49% | 4.24% |
| Age 85 and over | 6.62% | 1.09% | 1.78% |
| RACE | | | |
| White | 78.67% | 50.48% | 72.41% |
| Black | 1.61% | 1.75% | 12.61% |
| Asian | 12.51% | 39.16% | 4.75% |
| American Indian | 0.24% | 0.17% | 0.95% |
| Other | 6.96% | 8.43% | 9.28% |
| Hispanic | 91.57% | 76.67% | 16.35% |
| Non-Hispanic | 8.43% | 23.33% | 83.65% |
| FAMILY | | | |
| Married, w/children | 29.48% | 40.46% | 30.42% |
| Married, no children | 52.55% | 39.09% | 42.46% |
| Single, w/children | 7.97% | 9.34% | 14.39% |
| Single, no children | 10.01% | 11.11% | 12.73% |
| Divorced | 10.42% | 9.07% | 10.62% |
| Separated | 4.09% | 4.52% | 4.97% |
| Widowed | 10.08% | 3.64% | 6.14% |
| Now Married | 47.81% | 46.91% | 46.32% |
| Never Married | 27.59% | 35.85% | 31.95% |
