percentages, and how to present them with data

[guanza]

This is very basic mathematics but I'm having trouble figuring this out. khanacademy was of no help really.
While I know how to manipulate percentages, I have no idea why some online calculators and some threads over at quora and superuser seem
to subtract one time the whole amount using the 1.

What is the percentage increase/decrease = https://percentagecalculator.net/

Percentage Difference Calculator + Percentage Change Calculator

Percentage Calculator

This free percentage calculator computes a number of values involving percentages, including the percentage difference between two given values.

www.calculator.net

if I personally wanted to find out the increase between two numbers I would calculate this as follows (basically using the Rule of three):
73/23 = 3,17 *100 = 317%
and I would leave it at that.

while I never calculate like this (as follows) I assume most people put in the calculator 23*317% = 72.91
so my calculation above would make sense.
but if I were to represent my data and subtract one whole number and use the 217% like these calculators seem to suggest
I would be missing a whole number if I were to input this with the 217% in the calculator.

what am I missing?

 

[Dr.Peterson]

if I personally wanted to find out the increase between two numbers I would calculate this as follows (basically using the Rule of three):
73/23 = 3,17 *100 = 317%
and I would leave it at that.

You seem to be missing the difference between "percentage of" and "percentage change".

It is true that 73 is 317% of 23. But the percentage change from 23 to 73 means the change (73 - 23 = 50) as a percent of the starting number, 23: 50/23 = 2.17 = 217%.

When it is the latter you want, then the quick way is to just subtract 100% from the 317%. But if you want the percent of, you don't do that.

What you calculated simply is not what you called it. The increase is 50, and the percent increase is 217%.

 

[guanza]

I'm sometimes compiling online lists and I have been subtracting the 1 (or 100%) at the end.
now I remember too why I went with the increase and why you add 100 to the operation.
if you calculate 100% on a number you have to add another 100% if you want the percentage increase to register and/or to keep it as one calculation.
23*100% = 23 .. or 23*1
23*200% = 46 .. or 23*2
but yea, basically what you said @Dr.Peterson

alright @Dr.Peterson tyvm. you've helped me very much.


difference between percentage of and percentage change
percentages. why do you add another 100?