Given the nature of the Internet, it's easy to immerse yourself in all sorts of data related to the global pandemic, but finding the most recent data and really understanding what it means for you can still be a challenge. We built COVID Daily Digest to highlight the info you need to make healthy decisions as you go about your day.

The data gets updated daily, so check back frequently to keep an eye on the trends. Use the slider to scroll back through time and see how the situation has changed.

Infection and mortality data for the United States comes from the COVID-19 API maintained by *The Atlantic*. International case data comes from a database maintained by the World Health Organization.

US state population data is pulled from Wikipedia. Populations for other countries come from Worldometer. Baseline mortality rates are provided by the CDC. If you're curious about how some of the fields are calculated or think I made a mistake, send a note to rob@lazy8studios.com.

Many of the numbers you see in the digest come directly from the positive test results and deaths reported by each state. Some studies have suggested that both value greatly underrepresent the actual numbers, incluing this study by MIT from July, suggesting that true cases are 8 times higher than reported and that deaths are 1.4 time higher.

In other words, all the numbers you see here are likely to underestimate the present danger.

To calculate how many people would need to be in a room to exceed a 50% probability that at least one is currently contagious, I start with the CDC guidelines that suggest an individual with COVID can be contagious for 10 days since symptom onset. The reality is that the window of contagion will vary between individuals.

With these assumptions, I compute the probability that any individual is contagious, *p*, as the sum of positive cases over the last 10 days divided by a state's population. The means that the probabilty someone isn't contagious is 1 - *p*. We can then use an exponential equation to add people to a room and solve for when the probabilty that nobody is contagious drops below 50%: (1-*p*)^{n} = 0.5. Solving for *n*, we get *n* = ln 0.5 / ln(1-*p*).

For charts that use moving averages, each point represents the average from the current day and the 6 prior days.

Rob Jagnow

Chris Melamed

This is a nights-and-weekends project by Rob Jagnow & Chris Melamed. Interested in seeing related projects? Check out The Politics of COVID.