As of the census[REF] of 2000, there were 627,846 people, 242,040 households, and 158,778 families residing in the county.
In the county, the population was spread out with 25.10% under the age of 18, 10.70% from 18 to 24, 36.50% from 25 to 44, 20.40% from 45 to 64, and 7.40% who were 65 years of age or older.