-79.07% is the change from 86 to 18
Calculation steps:
[( 18 - 86 ) ÷ 86] x 100 = -79.07%
Formula
Percentage change = [(18 - 86) / 86] x 100
Subtract the new number by the original number
18 - 86 = -68
-68 ÷ 86 = -0.7906976744186046
-0.7906976744186046 x 100 = -79.07%