-77.93% is the change from 820 to 181
Calculation steps:
[( 181 - 820 ) ÷ 820] x 100 = -77.93%
Formula
Percentage change = [(181 - 820) / 820] x 100
Subtract the new number by the original number
181 - 820 = -639
-639 ÷ 820 = -0.7792682926829269
-0.7792682926829269 x 100 = -77.93%