-68.74% is the change from 531 to 166
Calculation steps:
[( 166 - 531 ) ÷ 531] x 100 = -68.74%
Formula
Percentage change = [(166 - 531) / 531] x 100
Subtract the new number by the original number
166 - 531 = -365
-365 ÷ 531 = -0.687382297551789
-0.687382297551789 x 100 = -68.74%