-12.2% is the change from 615 to 540
Calculation steps:
[( 540 - 615 ) ÷ 615] x 100 = -12.2%
Formula
Percentage change = [(540 - 615) / 615] x 100
Subtract the new number by the original number
540 - 615 = -75
-75 ÷ 615 = -0.12195121951219512
-0.12195121951219512 x 100 = -12.2%