Answer based on context:

The population was spread out with 39,128 people (20.6%) under the age of 18, 15,906 people (8.4%) aged 18 to 24, 54,024 people (28.4%) aged 25 to 44, 53,978 people (28.4%) aged 45 to 64, and 26,956 people (14.2%) who were 65 years of age or older. The median age was 40.2 years. For every 100 females, there were 98.5 males. For every 100 females age 18 and over, there were 96.6 males.

Which age group is smaller: under the age of 18 or 18 to 24?
18 to 24