This map comes from the Detroit Department of Health’s report titled “A birdseye view of Detroit’s health status for the year 1922.” The city existed as 23 districts with “populations sufficiently large to make the comparison of rates worth while.” Infant mortality was tracked the same way we track it today as, “deaths under 1 year … per 1,000 living births.”

Some things don’t change which makes it possible to track improvements. Detroit’s infant mortality rate has improved significantly from 1922, but there is still work to be done in 2016.