-7.6% is the change from 250 to 231
Calculation steps:
[( 231 - 250 ) ÷ 250] x 100 = -7.6%
Formula
Percentage change = [(231 - 250) / 250] x 100
Subtract the new number by the original number
231 - 250 = -19
-19 ÷ 250 = -0.076
-0.076 x 100 = -7.6%
Example