-36.59% is the change from 615 to 390
Calculation steps:
[( 390 - 615 ) ÷ 615] x 100 = -36.59%
Formula
Percentage change = [(390 - 615) / 615] x 100
Subtract the new number by the original number
390 - 615 = -225
-225 ÷ 615 = -0.36585365853658536
-0.36585365853658536 x 100 = -36.59%