According to the 2010 United States Census estimate, the city population grew to 99,685 and the Quad Cities metropolitan area grew to 379,690. As of the 2000 census, there were 98,359 people, 39,124 households, and 24,804 families residing in the city. The population density was 1,566.5 people per square mile (604.8/km²). There were 41,350 housing units at an average density of 658.5 per square mile (254.3/km²). Davenports population density is 30 times the average density of Iowa and 20 times the average density of the United States. However, it is about a third less than Des Moines and 20 percent less than Cedar Rapids, the only two cities in Iowa with higher populations than Davenport. Sioux City, the next city smaller than Davenport in population, has a density of 5 people more per square mile.. How many more households residing in Quad Cities metropolitan area than families?