According to the 2009 American Community Survey, the average household size was 2.11, and the average family size was 3.21. Approximately 59.4% of the population over the age of 25 have a bachelor's degree or higher. Approximately 27.0% of the population is foreign-born, and 61.7% of the population over the age of 5 speak only English at home. People of Irish ancestry make up 7.8% of the population, while Italian Americans make up 6.8% of the population. German Americans and Russian Americans make up 7.2% and 6.2% of the population respectively.