Average life expectancy in Chilton County is 73.8 years, lower than the state average of 75.3 and the national average of 77.9 years, according to the 2010 Alabama Health Data Sheet released by the Auburn University at Montgomery Center for Demographic Research and the state health department.

Life expectancy is the average number of years a newborn, or someone at a given age, would be expected to live if health and living conditions remain constant throughout his or her lifetime. The most recent available figures are from 2008.

Alton Stone, a research analyst with the Alabama Department of Public Health’s Center for Health Statistics, said mortality rate and age of population are factors when determining life expectancy.

According to the data sheet, 13 percent of Chilton County residents were age 65 or older, while 20 percent of residents were under age 20. The estimated county population for 2008 was 42,444.

“Shelby County has one of the highest life expectancies because a large number of younger people have moved into the area,” Stone said.

Neighboring Shelby County had an average life expectancy of 78.6 years, higher than the state and national averages.

The data sheet also includes infant mortality numbers. For Chilton County, the infant mortality rate of 13.1 was higher than the state rate of 9.5 percent and nearly double the national average.

There were eight infant deaths in Chilton County in 2008.

The infant mortality rate is calculated by dividing the number of infant deaths (under age 1) by the number of live births times 1,000.

Other statistics include:

The percentage of Chilton County residents below poverty was 18.3.

The county’s marriage and divorce rates were 9.9 percent and 5.6 percent, respectively.

The percentage of births to unmarried women was 24.6.