There were 810,388 households out of which 28.61% had children under the age of 18 living with them, 42.80% were Marriage living together, 15.28% had a female householder with no husband present, and 36.67% were non-families. 28.79% of all households were made up of individuals and 11.07% (3.31% male and 7.76% female) had someone living alone who was 65 years of age or older. The average household size was 2.52 and the average family size was 3.14.. which household was least common?