Link to live chart: COVID-19 Trends
This chart helps us see which countries might be close to having the spread of the coronavirus under control. It’s based on a model (Farr’s Law of Epidemics, references here and here) that suggests a virus like this might follow a standard normal distribution (often called a “bell curve”). If this is true, it might lend some predictability to how this virus is spreading.
(Note: I’m not suggesting here Farr’s Law of Epidemics holds true in all or even most situations involving the spread of a communicable disease. That is something you need to judge for yourself. But I am suggesting Farr’s Law is a useful basis for investigating whether the coronavirus and COVID-19 follow a pattern with enough consistency to help us make better decisions about how to address them effectively.)
This chart uses a metric called “Days from Peak” which tells us how many days have passed since a country experienced its highest number of new cases per day. If the above idea is valid, a peak indicates the rise is over and the decline (of new cases) has begun.
How to Use this Chart
The countries in the upper left (gray) chart are listed in order of their days from the highest number of daily new cases. Remember, higher is better because it suggests the current peak will be the final peak.
The upper right (orange) chart shows the total number of confirmed cases for the country. This is important because the higher number of cases gives us more events, making the information (we hope) more accurate. If you see a small number here, it might mean the virus’ spread in that country is just getting started.
The bottom (blue) chart shows the number of new cases per day for the country you select. (Select a country by clicking on it in either the gray or the orange chart). This enables you to see the actual pattern of spread for that country. Does it look like a bell curve? If so, does that tell us anything useful about how much longer the spread might continue for that country?
China and South Korea both show new daily case patterns that roughly resemble a bell curve. Denmark and Sweden each show a slightly choppier pattern but with more time, they too might see something close to a bell curve.
If you see value in this model, please use it to better understand what’s happening. Evaluate it and draw your own conclusions. And share it with others who might do the same.
You can go directly to the live graphic here. Thanks to the nice people at Tableau Software for hosting this.