-90.7% is the change from 86 to 8
Calculation steps:
[( 8 - 86 ) ÷ 86] x 100 = -90.7%
Formula
Percentage change = [(8 - 86) / 86] x 100
Subtract the new number by the original number
8 - 86 = -78
-78 ÷ 86 = -0.9069767441860465
-0.9069767441860465 x 100 = -90.7%