Big thanks to @BenMarten for his excellent collection and comparison of masks and cases data. We took his data and embedded it here in several sheets. Feel free to play around with the filters on the right and let us know what information you find. The data takes county-level cases and deaths (per 100K population for COVID-19) and maps then as a correlation against the survey provided by the New York Times as to mask use across the country.
The survey was conducted in the middle of July and we’ve present the dates to July 15th through Sept 15th.
The line shows a positive or negative correlation. If masks do indeed work you would expect to see a line sloping downward. Hover over the line to get your R-square and P values.