-36.44% is the change from 815 to 518
Calculation steps:
[( 518 - 815 ) ÷ 815] x 100 = -36.44%
Formula
Percentage change = [(518 - 815) / 815] x 100
Subtract the new number by the original number
518 - 815 = -297
-297 ÷ 815 = -0.36441717791411044
-0.36441717791411044 x 100 = -36.44%