Monthly case counts are based on specimen collection date for COVID-19 PCR Test that resulted in a confirmed positive case. This is different from the methodology for the daily dashboard, which is based on "active confirmed cases".
The above data been compiled by the Winchester Health Department, with data from the Massachusetts Virtual Epidemiological Network (MAVEN). Numbers are based on the most current available data, which is subject to change. Discrepancies with state reporting are possible due to timing of data availability. State reporting can be found here