-30.83% is the change from 240 to 166
Calculation steps:
[( 166 - 240 ) ÷ 240] x 100 = -30.83%
Formula
Percentage change = [(166 - 240) / 240] x 100
Subtract the new number by the original number
166 - 240 = -74
-74 ÷ 240 = -0.30833333333333335
-0.30833333333333335 x 100 = -30.83%