-99.02% is the change from 615 to 6
Calculation steps:
[( 6 - 615 ) ÷ 615] x 100 = -99.02%
Formula
Percentage change = [(6 - 615) / 615] x 100
Subtract the new number by the original number
6 - 615 = -609
-609 ÷ 615 = -0.9902439024390244
-0.9902439024390244 x 100 = -99.02%