| | Captain Cook, HI | Newcastle, CA | United States |
| Population | 4,087 | 1,505 | 329,725,481 |
| Female Population | 45.5% | 50.9% | 50.5% |
| Male Population | 54.5% | 49.1% | 49.5% |
| Median Age | 36.5 | 40.9 | 38.4 |
| space3 | | | |
| Population - 2010 | 3,168 | 1,116 | 309,327,143 |
| Population - 2000 | 3,206 | 1,145 | 285,036,114 |
| Population - 1990 | 2,595 | 1,048 | 251,960,433 |
| Pop. 2000 to Now | 27.7% | 19.0% | 15.6% |
| Pop. 1990 to Now | 57.8% | 30.1% | 30.8% |
| space4 | | | |
| Population Density | 317.9 | 629.2 | 93.4 |
| Land Area | 12.9 | 2.4 | 3,531,905.4 |
| Water Area | 0.0 | 0.0 | 264,836.8 |
| space | | | |
| Est. Total Population By Age | | | |
| | Captain Cook, HI | Newcastle, CA | United States |
| Age 0 to 4 | 7.9% | 2.6% | 5.9% |
| Age 5 to 9 | 5.4% | 5.8% | 6.1% |
| Age 10 to 14 | 9.2% | 8.9% | 6.6% |
| Age 15 to 17 | 3.3% | 1.7% | 3.9% |
| Age 18 to 20 | 2.8% | 0.5% | 4.0% |
| Age 21 to 24 | 5.6% | 1.2% | 5.2% |
| Age 25 to 34 | 13.7% | 17.9% | 13.8% |
| Age 35 to 44 | 11.6% | 17.2% | 12.9% |
| Age 45 to 54 | 6.0% | 4.5% | 12.6% |
| Age 55 to 59 | 4.8% | 3.5% | 6.7% |
| Age 60 to 64 | 8.3% | 7.6% | 6.3% |
| Age 65 to 74 | 19.6% | 18.9% | 9.6% |
| Age 75 to 84 | 1.6% | 7.0% | 4.5% |
| Age 85 and over | 0.2% | 2.7% | 1.9% |
| space1 | | | |
| Race | | | |
| | Captain Cook, HI | Newcastle, CA | United States |
| White | 28.4% | 73.4% | 59.4% |
| Black | 0.0% | 0.0% | 12.2% |
| Asian | 12.9% | 0.7% | 5.6% |
| Native American | 0.0% | 0.3% | 0.6% |
| Hawaiian, Pacific Islander | 12.1% | 0.0% | 0.2% |
| Other | 0.0% | 0.0% | 0.4% |
| Two or More Races | 13.6% | 8.6% | 3.2% |
| Hispanic | 33.0% | 17.1% | 18.4% |
| space2 | | | |
| Marriage & Family | | | |
| | Captain Cook, HI | Newcastle, CA | United States |
| Married Population | 43.9% | 44.7% | 49.8% |
| Currently Married | 41.9% | 44.6% | 48.0% |
| Married but Separated | 2.0% | 0.1% | 1.8% |
| Single Population | 56.1% | 55.3% | 50.2% |
| Never Married | 34.2% | 29.7% | 33.8% |
| Divorced | 17.1% | 16.2% | 10.8% |
| Widowed | 4.8% | 9.4% | 5.6% |
| space5 | | | |
| Household Size | 3.73 | 2.36 | 2.60 |
| Households | 1,096 | 634 | 124,010,992 |
| Family Households | 865 | 397 | 80,755,759 |
| Married couple, w/children | 41.7% | 21.2% | 30.5% |
| Married couple, no children | 26.1% | 45.6% | 42.9% |
| Non Family Households | 231 | 237 | 43,255,233 |
| Single householder, w/children | 13.5% | 12.1% | 15.8% |
| Single householder, no children | 18.6% | 21.2% | 10.8% |