Question

How to convert percent increase or decrease into a multiplier

Answer 1

In case of an increase use this formula
$mutiplier = 1 + \frac{\%}{100}$
So if the percentage of increase of 6%, the multiplier will be
$1 + \frac{6}{100} = 1.06$

In case of a decrease, the formula is mostly the same.
$mutiplier = 1 - \frac{\%}{100}$
So if the percentage of decrease is 6%, the multiplier will be
$1 - \frac{6}{100} = 0.94$