Testing trends tool
These charts lay out the key metrics for understanding the reach and severity of COVID-19 in a given area: number of new daily cases, tests per 100,000 people (testing rate), and percentage of tests that are positive (positivity rate).
As testing capacity increases, considering confirmed new cases, testing rates, and percent positivity together gives us a fuller picture of COVID-19 in a particular state or region. Under these conditions and stable testing practices, trends in daily cases can be cautiously interpreted as trends in transmission of the virus. Leaders can then make informed decisions about lifting social distancing and other transmission control measures.
JOHNS HOPKINS: Coronavirus Resource Center