-39.16% is the change from 166 to 101
Calculation steps:
[( 101 - 166 ) ÷ 166] x 100 = -39.16%
Formula
Percentage change = [(101 - 166) / 166] x 100
Subtract the new number by the original number
101 - 166 = -65
-65 ÷ 166 = -0.39156626506024095
-0.39156626506024095 x 100 = -39.16%