-20.98% is the change from 615 to 486
Calculation steps:
[( 486 - 615 ) ÷ 615] x 100 = -20.98%
Formula
Percentage change = [(486 - 615) / 615] x 100
Subtract the new number by the original number
486 - 615 = -129
-129 ÷ 615 = -0.2097560975609756
-0.2097560975609756 x 100 = -20.98%