-89.27% is the change from 615 to 66
Calculation steps:
[( 66 - 615 ) ÷ 615] x 100 = -89.27%
Formula
Percentage change = [(66 - 615) / 615] x 100
Subtract the new number by the original number
66 - 615 = -549
-549 ÷ 615 = -0.8926829268292683
-0.8926829268292683 x 100 = -89.27%