-97.91% is the change from 815 to 17
Calculation steps:
[( 17 - 815 ) ÷ 815] x 100 = -97.91%
Formula
Percentage change = [(17 - 815) / 815] x 100
Subtract the new number by the original number
17 - 815 = -798
-798 ÷ 815 = -0.9791411042944785
-0.9791411042944785 x 100 = -97.91%