As with many cities in America's "rust-belt", population in the city limits of Cincinnati declined from 1950 to 2010. The trend surprisingly reversed with the publication of the 2020 Census showing a 4.2% increase. While one can find many explanations for this reversal, an interesting one appears to be the proximity of growing census tracts (green) to private athletic facilities (blue). According to the Countywide Parks and Greenspaces layer obtained from the Cincinnati Area GIS website, these included country clubs, tennis clubs, swim clubs, and even a "sports mall"
Find out more about the data included in this project, including the metadata. Vist the github repository: ActiveCincinnati