So far my daily charts of coronavirus growth have tracked confirmed cases, but there’s an obvious problem with this: if a country has a weak testing program it will artificially reduce the number of cases. Can you really compare Germany, which has tested 2,000 people per million, with the United States, which has tested only 300 per million? Won’t the US numbers look artificially low just because we aren’t finding them via testing?
Maybe, although the evidence is a little thin and there are reasons to think it might not make a big difference. Still, it’s a dubious metric (LA County, for example, has given up on most testing altogether) and I always planned to eventually switch to tracking deaths instead of cases. I’ve been holding off only because the current numbers are still low enough that there’s a fair amount of statistical noise in the data.
But we’re getting pretty close, so today I’m making the switch. It might be a little too early, but not by much. What you’ll see is that most countries are on track to follow Italy, but there are two exceptions below the trendline: Switzerland and the United States. In our case, we’re at about one-third the level Italy recorded at a comparable date. That’s a hopeful sign, but keep in mind that it might be just an artifact of our large population. Only time will tell.
Here’s how to read the charts: Let’s use France as an example. For them, Day 0 was March 5, when they surpassed one death per 10 million by recording their sixth death. They are currently at Day 15; total deaths are at 75x their initial level; and they have recorded a total of 6.7 deaths per million so far. As the chart shows, this is very close to where Italy was on their Day 15.
The raw data from Johns Hopkins is here.