-20% is the change from 540 to 432
Calculation steps:
[( 432 - 540 ) ÷ 540] x 100 = -20%
Formula
Percentage change = [(432 - 540) / 540] x 100
Subtract the new number by the original number
432 - 540 = -108
-108 ÷ 540 = -0.2
-0.2 x 100 = -20%
Example