New U.S. Census Bureau estimates say Detroit’s population continued its decline, knocking it off the list of the nation’s 20 most populous cities. Figures released Thursday say Detroit’s population was 677,116 last summer, down 3,107 from the previous year and putting in 21st on the list. The Detroit News reports the Census Bureau says the last time Detroit wasn’t in the Top 20 was 1850, when it was 30th.