San Francisco At Night, California, United States

There were 345,811 households, out of which 63,577 (18.4%) had children under the age of 18 living in them, 109,437 (31.6%) were opposite-sex married couples living together, 28,844 (8.3%) had a female householder with no husband present, 12,748 (3.7%) had a male householder with no wife present. There were 21,677 (6.3%) unmarried opposite-sex partnerships, and 10,384 (3.0%) same-sex married couples or partnerships. 133,366 households (38.6%) were made up of individuals and 34,234 (9.9%) had someone living alone who was 65 years of age or older. The average household size was 2.26. There were 151,029 families (43.7% of all households); the average family size was 3.11.
The population was spread out with 107,524 people (13.4%) under the age of 18, 77,664 people (9.6%) aged 18 to 24, 301,802 people (37.5%) aged 25 to 44, 208,403 people (25.9%) aged 45 to 64, and 109,842 people (13.6%) who were 65 years of age or older. The median age was 38.5 years. For every 100 females there were 102.9 males. For every 100 females age 18 and over, there were 102.8 males.
There were 376,942 housing units at an average density of 1,625.5 per square mile (627.6/km²), of which 123,646 (35.8%) were owner-occupied, and 222,165 (64.2%) were occupied by renters. The homeowner vacancy rate was 2.3%; the rental vacancy rate was 5.4%. 327,985 people (40.7% of the population) lived in owner-occupied housing units and 452,986 people (56.3%) lived in rental housing units.
The California Department of Finance estimated the population at 856,095, as of January 1, 2010. With over 17,000 people per square mile, San Francisco is the second-most densely populated major American city (among cities greater than 200,000 population). San Francisco is the traditional focal point of the San Francisco Bay Area and forms part of the San Francisco-Oakland-Fremont Metropolitan Statistical Area and the greater San Jose-San Francisco-Oakland Combined Statistical Area (CSA) whose population is over seven million, making it the fifth largest in the United States as of the 2000 Census.