1. COVID-19 cases and deaths, metropolitan and nonmetropolitan counties over time: (update) Author(s): Ullrich, Fred, authorMueller, Keith, author Publication: Iowa City, IA : Rural Policy Research Institute, February 2022 Subject(s): COVID-19 -- epidemiologyCOVID-19 -- mortalityRural Population -- statistics & numerical dataUrban Population -- statistics & numerical dataUnited States