-89.87% is the change from 819 to 83
Calculation steps:
[( 83 - 819 ) ÷ 819] x 100 = -89.87%
Formula
Percentage change = [(83 - 819) / 819] x 100
Subtract the new number by the original number
83 - 819 = -736
-736 ÷ 819 = -0.8986568986568987
-0.8986568986568987 x 100 = -89.87%