evidence: There was a major decline in the case-fatality rate — the number of coronavirus deaths divided by known cases — compared to an earlier phase in the epidemic. However, "groundbreaking therapies" are only part of the reason. One factor in a lower case-fatality rate is the huge increase in coronavirus testing. In the first weeks and months of the outbreak, testing focused on those who were more seriously ill, including nursing home residents. That kept the case-fatality rate high. By the time Operation Warp Speed had announced its scope and leadership, most of the decline in the case-fatality rate had already occurred.