-18.37% is the change from 615 to 502
Calculation steps:
[( 502 - 615 ) ÷ 615] x 100 = -18.37%
Formula
Percentage change = [(502 - 615) / 615] x 100
Subtract the new number by the original number
502 - 615 = -113
-113 ÷ 615 = -0.183739837398374
-0.183739837398374 x 100 = -18.37%