-71.5% is the change from 821 to 234
Calculation steps:
[( 234 - 821 ) ÷ 821] x 100 = -71.5%
Formula
Percentage change = [(234 - 821) / 821] x 100
Subtract the new number by the original number
234 - 821 = -587
-587 ÷ 821 = -0.7149817295980512
-0.7149817295980512 x 100 = -71.5%