Answer based on context:

As of the census of 2000, there were 1,623,018 people, 654,445 households, and 411,645 families residing in the county. The population density was 1,346 people per square mile (520/km). There were 741,043 housing units at an average density of 615 per square mile (237/km). The racial makeup of the county was 70.57% Race (United States Census) (58% were Non-Hispanic), 20.54% Race (United States Census) or Race (United States Census), 0.24% Race (United States Census), 2.25% Race (United States Census), 0.06% Race (United States Census), 3.00% from Race (United States Census), and 3.35% from two or more races. 16.74% of the population were Race (United States Census) or Race (United States Census) of any race.

Were there more housing units or households in the county in the 2000 census?
housing units