South Dakota's Youth Population Stabilizes As Nation's Shrinks
South Dakota's population below age 18, as a percentage of the total population, had been shrinking in previous years, but the trend appears to have stabilized. In contrast, the proportion of youth in the national population continues its slow decline.
The percentage of South Dakotan children under 18 has remained steady at 24.6 percent since 2012, down slightly from 28.5 percent in 1990 and 26.8 percent in 2000. Nationwide, those under age 18 made up 22.8 percent of the total population in 2016, down from 23.1 percent in 2014 and from 25.7 percent in 2000.
While the overall percentage of children under 18 in South Dakota has decreased, there were 14,825 more children in the state in 2016 than there were in 1990—213,287 compared to 198,462. At the same time, the number of adult South Dakotans grew by almost 150,000, from 497,542 in 1990 to 652,167 in 2016.
Of the state’s metropolitan and micropolitan areas, the micropolitan areas had the smallest percentage children under 18 at 22.4 percent. Rural areas had the largest proportion of children at 26.6 percent.
Custer County, which was also the state’s oldest county in 2016, had the lowest percentage of children in the state at 15.9 percent. Todd County had the highest percentage at 40.8 percent.
As a proportion of the state's total population, South Dakota children ages 5 to 9 as well as those 10 to 14 have dropped the most, decreasing by 1.4 and 1.3 percent, respectively, from 1990 to 2016. South Dakotans aged 0 to 4 and 15 to 19 both decreased by just 0.7 percent over the same time period.
In 2000, the 15 to 19 age group had the largest share of the overall population, at 8.3 percent. But by 2010, the 0 to 4 cohort had become dominant and represented 7.3 percent of the state population as compared to 7.1 percent for the 15 to 19 cohort. The most recent 2016 data indicates that the 0 to 4 cohort is still the largest in the state, representing 7.1 percent of the South Dakota population. That cohort was followed closely by the 5- to 9-year-olds at 7.0 percent, and then by the 15 to 19 and 10 to 14 cohorts which both represented 6.6 percent of the state's population.