-86.87% is the change from 99 to 13
Calculation steps:
[( 13 - 99 ) ÷ 99] x 100 = -86.87%
Formula
Percentage change = [(13 - 99) / 99] x 100
Subtract the new number by the original number
13 - 99 = -86
-86 ÷ 99 = -0.8686868686868687
-0.8686868686868687 x 100 = -86.87%