At the census of 2000, there had been 37,640 people, 13,192 households, and 10,659 families residing in the city. The population density was 957.0 people per square mile (369.5/km). There were 13,922 housing units at an average density of 354.0 per square mile (136.7/km). The median income for a household in the city as of 2000 was $64,156, and the median income for a family was $70,748 (these figures had risen to $83,706 and $92,096 respectively as of a 2007 estimate). Males had a median income of $49,359 versus $34,570 for females. The per capita income for the city was $26,306. About 3.4% of families and 4.7% of the population were below the poverty line, including 6.1% of those under age 18 and 3.5% of those age 65 or over.