King County Historical Household and Family Data
ACS 2010-2014 data
Total population: 2,008,997
| King County | Washington | U.S. | |
| Total Households | 808,729, 100% | 2,645,396 | 116,211,092 |
| Average Household Size | 2.44, see rank | 2.55 | 2.63 |
| 1 Person Households | 252,147, 31.18%, see rank | 27.79% | 27.57% |
| 2 or More Person Households | 556,582, 68.82%, see rank | 72.21% | 72.43% |
| Family Households (Families) | 478,964, 59.22%, see rank | 64.48% | 66.22% |
| Average Family Size | 3.19, see rank | 3.23 | 3.32 |
| Married-Couple Family | 375,096, 46.38%, see rank | 49.73% | 48.42% |
| Nonfamily Households | 329,765, 40.78%, see rank | 35.52% | 33.78% |
US Census 2010 data
Total population: 1,931,249
| King County | Washington | U.S. | |
| Total Households | 789,232, 100% | 2,620,076 | 116,716,292 |
| Average Household Size | 2.40, see rank | 2.51 | 2.58 |
| 1 Person Households | 244,699, 31.00%, see rank | 27.16% | 26.74% |
| 2 or More Person Households | 544,533, 69.00%, see rank | 72.84% | 73.26% |
| Family Households (Families) | 461,510, 58.48%, see rank | 64.40% | 66.43% |
| Average Family Size | 3.05, see rank | 3.06 | 3.14 |
| Married-Couple Family | 357,491, 45.30%, see rank | 49.19% | 48.42% |
| Nonfamily Households | 327,722, 41.52%, see rank | 35.60% | 33.57% |
ACS 2008-2012 data
Total population: 1,940,777
| King County | Washington | U.S. | |
| Total Households | 796,555, 100% | 2,619,995 | 115,226,802 |
| Average Household Size | 2.39, see rank | 2.52 | 2.61 |
| 1 Person Households | 251,453, 31.57%, see rank | 27.74% | 27.45% |
| 2 or More Person Households | 545,102, 68.43%, see rank | 72.26% | 72.55% |
| Family Households (Families) | 466,381, 58.55%, see rank | 64.49% | 66.47% |
| Average Family Size | 3.14, see rank | 3.18 | 3.29 |
| Married-Couple Family | 366,569, 46.02%, see rank | 49.98% | 48.97% |
| Nonfamily Households | 330,174, 41.45%, see rank | 35.51% | 33.53% |
ACS 2006-2010 data
Total population: 1,879,189
| King County | Washington | U.S. | |
| Total Households | 781,977, 100% | 2,577,375 | 114,235,996 |
| Average Household Size | 2.36, see rank | 2.49 | 2.59 |
| 1 Person Households | 249,937, 31.96%, see rank | 27.74% | 27.24% |
| 2 or More Person Households | 532,040, 68.04%, see rank | 72.26% | 72.76% |
| Family Households (Families) | 456,029, 58.32%, see rank | 64.62% | 66.75% |
| Average Family Size | 3.10, see rank | 3.14 | 3.25 |
| Married-Couple Family | 357,285, 45.69%, see rank | 50.17% | 49.60% |
| Nonfamily Households | 325,948, 41.68%, see rank | 35.38% | 33.25% |
ACS 2005-2009 data
Total population: 1,858,788
| King County | Washington | U.S. | |
| Total Households | 767,486, 100% | 2,512,327 | 112,611,029 |
| Average Household Size | 2.38, see rank | 2.52 | 2.60 |
| 1 Person Households | 246,696, 32.14%, see rank | 27.81% | 27.32% |
| 2 or More Person Households | 520,790, 67.86%, see rank | 72.19% | 72.68% |
| Family Households (Families) | 446,678, 58.20%, see rank | 64.50% | 66.67% |
| Average Family Size | 3.13, see rank | 3.18 | 3.27 |
| Married-Couple Family | 351,370, 45.78%, see rank | 50.27% | 49.71% |
| Nonfamily Households | 320,808, 41.80%, see rank | 35.50% | 33.33% |
US Census 2000 data
Total population: 1,737,034
| King County | Washington | U.S. | |
| Total Households | 710,916, 100% | 2,271,398 | 105,480,101 |
| Average Household Size | 2.39, see rank | 2.53 | 2.59 |
| 1 Person Households | 217,163, 30.55%, see rank | 26.17% | 25.82% |
| 2 or More Person Households | 493,753, 69.45%, see rank | 73.83% | 74.18% |
| Family Households (Families) | 419,959, 59.07%, see rank | 66.00% | 68.06% |
| Average Family Size | 3.03, see rank | 3.07 | 3.14 |
| Married-Couple Family | 329,768, 46.39%, see rank | 52.04% | 51.66% |
| Nonfamily Households | 290,957, 40.93%, see rank | 34.00% | 31.94% |
* ACS stands for U.S. Census American Community Survey. According to the U.S. Census, if the date is a range, you can interpret the data as an average of the period of time.