Almost all of the data we compile is taken directly from the websites of state/territory public health authorities. When data is missing from these websites, we sometimes supplement available numbers with information from official press conferences with governors or other state authorities.
Individual state/territory data pages such as Wyoming’s, all of which are accessible from our main data page, include links at the top of the page to our data sources for that state. The “Best current data source” is usually the state or territory’s public health department’s coronavirus-specific response page, and additional data sources are usually coronavirus-specific data dashboards or public health department web pages. We are careful to make sure that we collect data from official state/territory sources.
As of March 14, 2020, each state page also includes timestamped snapshots of data sources. Click ”View screenshots” on any state page to see them.
We discuss changes, anomalies, and ambiguities in data sources in the public notes for every state on our main data page and on each state’s individual data page. Click “Read more state notes” to see them all.
To find the precise source of a particular data point, please refer to our public spreadsheet of source notes.
As we note in our FAQ, there are several reasons why The COVID Tracking Project data might not match the visible data on a state’s dashboard, including the presence of hidden data that we retrieve with a machine query, different data definitions, and time lag.
Read our article ”How We Source Our Data and Why It Matters” for more information.
Help us get better data
The COVID Tracking Project can’t offer official guidance to state health departments or compel states to report missing data. We’ve built a state grading system so that state governments and their constituents can see who’s doing well and who is underperforming. We’ve built a volunteer outreach team who are in contact with authorities in every state and territory. But in the end, all we can do is ask for better and more complete data—and then ask for it again. If you’d like to see better data, please contact your governor.