-83.68% is the change from 821 to 134
Calculation steps:
[( 134 - 821 ) ÷ 821] x 100 = -83.68%
Formula
Percentage change = [(134 - 821) / 821] x 100
Subtract the new number by the original number
134 - 821 = -687
-687 ÷ 821 = -0.8367844092570037
-0.8367844092570037 x 100 = -83.68%