The U.S. Census Bureau revealed findings from the 2020 census, and Washington County saw a 6.5 percent decrease in population over the last decade.
According to the interactive map, the total population in the county was reported to be 13,761. The amount is less than what was counted in the 2010 census, which was 14,716.
Other surrounding counties that reported population declines included Perry County (6.3 percent), St. Clair County (4.7 percent), Jefferson County (4.4 percent), Marion (4.3 percent) and Clinton County (2.4 percent).
The county with the highest decline in population was Alexander County with 36.4 percent or nearly 3,000 people. The 2010 population was 8,238, and in 2020, the census counted 5,240.
As a state, Illinois decreased 0.1 percent since 2010, reporting 12,812,508 people in the census.