-33.6% is the change from 250 to 166
Calculation steps:
[( 166 - 250 ) ÷ 250] x 100 = -33.6%
Formula
Percentage change = [(166 - 250) / 250] x 100
Subtract the new number by the original number
166 - 250 = -84
-84 ÷ 250 = -0.336
-0.336 x 100 = -33.6%