-77.95% is the change from 821 to 181
Calculation steps:
[( 181 - 821 ) ÷ 821] x 100 = -77.95%
Formula
Percentage change = [(181 - 821) / 821] x 100
Subtract the new number by the original number
181 - 821 = -640
-640 ÷ 821 = -0.7795371498172959
-0.7795371498172959 x 100 = -77.95%