growth rate (% increase of previous increase)

[mikeborozdin]

Context

We show a percentage increase in cases and deaths. That percentage is increase is calculated as (casesOnLastDay - casesOnPreviousDay) / casesOnLastDay.

There's a potential problem with it. We can hear in the news that, say, in the UK there's been the highest number of deaths on a single day - 1,000. So if each day from that one there are 1,000 more deaths on each single day, then our percentage increase would start to go down.

Indeed, although the number is terrifying it stays the same, while the total numbers keeps growing. Hence, it's share in total drops with every single day.

Possible solution

A better option would be to see how numbers grow in relation to the previous increase, a.k.a we can use this formula:

growthRate = absoluteIncreaseOnLastDay / absoluteIncreaseOnPreviousDay

In that case, with a constant number of 1,000 we'll see that the rate of growth is still 100%.

I think we should add this chart, but keep the existing one. It'll be useful to see how those numbers play with each other.

[mikeborozdin]

Solved by doing a growth rate of a moving average (over 7 days)