-37.5% is the change from 400 to 250
Calculation steps:
[( 250 - 400 ) ÷ 400] x 100 = -37.5%
Formula
Percentage change = [(250 - 400) / 400] x 100
Subtract the new number by the original number
250 - 400 = -150
-150 ÷ 400 = -0.375
-0.375 x 100 = -37.5%