-19.63% is the change from 815 to 655
Calculation steps:
[( 655 - 815 ) ÷ 815] x 100 = -19.63%
Formula
Percentage change = [(655 - 815) / 815] x 100
Subtract the new number by the original number
655 - 815 = -160
-160 ÷ 815 = -0.19631901840490798
-0.19631901840490798 x 100 = -19.63%