This discussion is a good example with perhaps some application to the
presentation of bee-related data.

This paper uses specific terms to describe the numbers.


A "rate of growth" is not a simple percentage change in the total infected
or dead.

A straightforward percentage change is:
 ( A2 - A1 / A1 ) * 100 = percentage change

Assuming only linear change, we can do this:
((A2 - A1 / ( T1 - T2)) /A 1) * 100 = linear growth rate, a linear rate of
change

But viral infections and not "linear".  They are exponential.  Very small
initial differences can create massive differences later, due to the
exponential spread of something like a virus.

There are guesstimate tools that dispense with the complex math, such as the
"Rule of 69.3", "Rule of 70", and "Rule of 72"  (69.3 is the best for
exponentials, in my view, because the natural log of 2 is roughly 0.693
(69.3%), so it best approximates "daily compounding" of compound interest
and other exponentials.  This uses the plain old "percent change" rather
than the "rate of growth".  The time to the doubling of the number of deaths
would be:

69.3 / the current percent killed
so 69.3 / 1 = 69.3
but 69.3 / 2 = 34.6
and 69.3 / 3 = 23.1

Also, percentage points are not percentages.  They are bigger.

If deaths increased by 5 percent from an original value of 20 percent, the
current death rate is then 21 percent (5% of the 20% figure). If you said it
increased by 5 percentage POINTS, the current rate would be 25 percent vs 20
percent.

And under it all, we have to remember that percent means "per hundred".
That's a lot of sickness and death.  If there are 1,000 Bee-L subscribers,
1% is 10 of us.

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