Grapheration day 17, pandemic day 23, day 94 since Wuhan. Yesterday we had our one millionth case of COVID-19, and that milestone shows up in today’s data update. Six countries experienced their first deaths from COVID-19 yesterday, including Kyrgyzstan, Mauritania, and Gibraltar. The disease has now killed over 50,000 people.

So far I’ve been presenting cases and deaths on two separate graphs, meaning you have had to look back and forth between two graphs to get the full story.

Well, sadly enough people have now died that you can now clearly see the story when they are graphed on the same axis.

The case fatality rate of COVID-19 worldwide is about 5 percent, meaning that approximately five out of every one hundred cases ends in death. For comparison, seasonal flu has a case fatality rate of less than 0.1 percent, and even smallpox’s was about one percent.

Comparing rates in different countries

That leads in to the other big disadvantage of showing cases and deaths in two separate graphs. Looking back and forth across two similar-looking graphs obscures an important part of the story: for a variety of reasons, different countries have different case fatality rates.

But we’re graphing several countries at once – if we tried to put cases and deaths as separate lines, the graph would quickly get very hard to read. So how can we show all these factors together on one graph?

I think I figured out an approach, and I’m interested in hearing your thoughts on this approach and whether you have any other ideas. I’ll plot cases only, but use the thickness of the line to represent the case fatality rate in each country. Now that the line thicknesses represent meaningful data, I had to make them all solid lines. Hopefully the line labels let you identify which country is which. To keep the total number of lines down, I removed France (sorry Greg). Also, Spain is now gold and Switzerland is now orange because reasons. And so:

I’m working on a few other visualizations as well.

Usual disclaimers: I’m not an expert, I’m just a guy on the Internet who likes to make graphs of things. I hope I’ve shown you some ways you can look into COVID-19 data for yourself. You can find the data from the European Centers for Disease Control’s Coronavirus Source Data site (download the CSV file from the “Full dataset” link). I have once again updated my Excel template (to adjust the line thicknesses), please use it.

Update tomorrow, and every day until this pandemic is over.