As of the 2000 United States Census there were 39,991 people, 19,828 households, and 12,174 families residing in the township. The population density was 932.3 people per square mile (359.9/km2). There were 22,288 housing units at an average density of 519.6 per square mile (200.6/km2). The racial makeup of the township was 97.10% White, 1.30% African American, 0.04% Native American, 0.45% Asian, 0.01% Pacific Islander, 0.43% from other races, and 0.66% from two or more races. Hispanic or Latino of any race were 2.33% of the population.