-91.11% is the change from 90 to 8
Calculation steps:
[( 8 - 90 ) ÷ 90] x 100 = -91.11%
Formula
Percentage change = [(8 - 90) / 90] x 100
Subtract the new number by the original number
8 - 90 = -82
-82 ÷ 90 = -0.9111111111111111
-0.9111111111111111 x 100 = -91.11%