-48.19% is the change from 166 to 86
Calculation steps:
[( 86 - 166 ) ÷ 166] x 100 = -48.19%
Formula
Percentage change = [(86 - 166) / 166] x 100
Subtract the new number by the original number
86 - 166 = -80
-80 ÷ 166 = -0.4819277108433735
-0.4819277108433735 x 100 = -48.19%