-32.5% is the change from 400 to 270
Calculation steps:
[( 270 - 400 ) ÷ 400] x 100 = -32.5%
Formula
Percentage change = [(270 - 400) / 400] x 100
Subtract the new number by the original number
270 - 400 = -130
-130 ÷ 400 = -0.325
-0.325 x 100 = -32.5%