Naperville is a city located in DuPage County, Illinois and Will County, Illinois. As of the 2000 census, the city had a total population of 128,358. Naperville has become something of an anchor city in the Chicagoland area.
Naperville was founded in 1831 by Joseph Naper. It served as the DuPage county seat briefly, a distinction which now belongs to nearby Wheaton, Illinois. A predominantly rural community for most of it's existence, Naperville experienced a population explosion in the 1980's and 1990's, nearly quadrupling in size as Chicagoland's urban sprawl brought corporations, jobs, and wealth to the area.
According to the United States Census Bureau, the city has a total area of 92.0 km² (35.5 mi²). 91.6 km² (35.4 mi²) of it is land and 0.4 km² (0.1 mi²) of it is water. The total area is 0.39% water.
As of the census of 2000, there are 128,358 people, 43,751 households, and 33,644 families residing in the city. The population density is 1,400.8/km² (3,628.3/mi²). There are 45,651 housing units at an average density of 498.2/km² (1,290.4/mi²). The racial makeup of the city is 85.19% White, 3.03% African American, 0.12% Native American, 9.64% Asian, 0.02% Pacific Islander, 0.75% from other races, and 1.25% from two or more races. 3.24% of the population are Hispanic or Latino of any race.
There are 43,751 households out of which 47.3% have children under the age of 18 living with them, 69.2% are married couples living together, 5.9% have a female householder with no husband present, and 23.1% are non-families. 18.8% of all households are made up of individuals and 4.5% have someone living alone who is 65 years of age or older. The average household size is 2.89 and the average family size is 3.37.
In the city the population is spread out with 31.8% under the age of 18, 6.4% from 18 to 24, 33.7% from 25 to 44, 21.9% from 45 to 64, and 6.2% who are 65 years of age or older. The median age is 34 years. For every 100 females there are 95.9 males. For every 100 females age 18 and over, there are 92.4 males.
The median income for a household in the city is $88,771, and the median income for a family is $101,590. Males have a median income of $75,905 versus $40,295 for females. The per capita income for the city is $35,551. 2.2% of the population and 1.6% of families are below the poverty line. Out of the total people living in poverty, 2.2% are under the age of 18 and 5.0% are 65 or older.