-90.5% is the change from 821 to 78
Calculation steps:
[( 78 - 821 ) ÷ 821] x 100 = -90.5%
Formula
Percentage change = [(78 - 821) / 821] x 100
Subtract the new number by the original number
78 - 821 = -743
-743 ÷ 821 = -0.904993909866017
-0.904993909866017 x 100 = -90.5%