-88.6% is the change from 798 to 91
Calculation steps:
[( 91 - 798 ) ÷ 798] x 100 = -88.6%
Formula
Percentage change = [(91 - 798) / 798] x 100
Subtract the new number by the original number
91 - 798 = -707
-707 ÷ 798 = -0.8859649122807017
-0.8859649122807017 x 100 = -88.6%