USA.com / Maryland / Frederick County / Rocky Ridge, MD / 21778 / Population and Races / Historical Household and Family Data
21778 Zip Code Historical Household and Family Data
ACS 2010-2014 data
Total population: 1,141
| 21778 Zip Code | Maryland | U.S. | |
| Total Households | 389, 100% | 2,155,983 | 116,211,092 |
| Average Household Size | 2.93, see rank | 2.67 | 2.63 |
| 1 Person Households | 94, 24.16%, see rank | 26.95% | 27.57% |
| 2 or More Person Households | 295, 75.84%, see rank | 73.05% | 72.43% |
| Family Households (Families) | 279, 71.72%, see rank | 67.07% | 66.22% |
| Average Family Size | 3.57, see rank | 3.35 | 3.32 |
| Married-Couple Family | 228, 58.61%, see rank | 47.68% | 48.42% |
| Nonfamily Households | 110, 28.28%, see rank | 32.93% | 33.78% |
US Census 2010 data
Total population: 1,094
| 21778 Zip Code | Maryland | U.S. | |
| Total Households | 409, 100% | 2,156,411 | 116,716,292 |
| Average Household Size | 2.67, see rank | 2.61 | 2.58 |
| 1 Person Households | 75, 18.34%, see rank | 26.11% | 26.74% |
| 2 or More Person Households | 334, 81.66%, see rank | 73.89% | 73.26% |
| Family Households (Families) | 310, 75.79%, see rank | 67.10% | 66.43% |
| Average Family Size | 3.00, see rank | 3.15 | 3.14 |
| Married-Couple Family | 255, 62.35%, see rank | 47.61% | 48.42% |
| Nonfamily Households | 99, 24.21%, see rank | 32.90% | 33.57% |
ACS 2008-2012 data
Total population: 1,345
| 21778 Zip Code | Maryland | U.S. | |
| Total Households | 482, 100% | 2,138,806 | 115,226,802 |
| Average Household Size | 2.79, see rank | 2.64 | 2.61 |
| 1 Person Households | 78, 16.18%, see rank | 27.12% | 27.45% |
| 2 or More Person Households | 404, 83.82%, see rank | 72.88% | 72.55% |
| Family Households (Families) | 404, 83.82%, see rank | 66.97% | 66.47% |
| Average Family Size | 3.14, see rank | 3.32 | 3.29 |
| Married-Couple Family | 307, 63.69%, see rank | 48.03% | 48.97% |
| Nonfamily Households | 78, 16.18%, see rank | 33.03% | 33.53% |
US Census 2000 data
Total population: 1,020
| 21778 Zip Code | Maryland | U.S. | |
| Total Households | 370, 100% | 1,980,859 | 105,480,101 |
| Average Household Size | 2.76, see rank | 2.61 | 2.59 |
| 1 Person Households | 54, 14.59%, see rank | 25.01% | 25.82% |
| 2 or More Person Households | 316, 85.41%, see rank | 74.99% | 74.18% |
| Family Households (Families) | 295, 79.73%, see rank | 68.62% | 68.06% |
| Average Family Size | 3.00, see rank | 3.13 | 3.14 |
| Married-Couple Family | 253, 68.38%, see rank | 50.21% | 51.66% |
| Nonfamily Households | 75, 20.27%, see rank | 31.38% | 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.