This data set provides the number of COVID-19 tests per day performed among Marin county residents and the percent positivity of those tests. The data comes from testing results reported to the California Department of Public health (CDPH). This is the same data used to calculate the county-level testing rate for the State Blueprint Metrics. Testing volume for the last two weeks is provisional and subject to change due to the lag in testing reporting.

Note: CDPH calculates Percent Positivity using a 7-day lag (on November 17 the most recent calculated date will be November 10), with a 7-day window (sum of all positive tests in prior 7 days divided by the sum of all tests in the prior 7 days).