-89.79% is the change from 823 to 84
Calculation steps:
[( 84 - 823 ) ÷ 823] x 100 = -89.79%
Formula
Percentage change = [(84 - 823) / 823] x 100
Subtract the new number by the original number
84 - 823 = -739
-739 ÷ 823 = -0.8979343863912516
-0.8979343863912516 x 100 = -89.79%