-87.73% is the change from 831 to 102
Calculation steps:
[( 102 - 831 ) ÷ 831] x 100 = -87.73%
Formula
Percentage change = [(102 - 831) / 831] x 100
Subtract the new number by the original number
102 - 831 = -729
-729 ÷ 831 = -0.8772563176895307
-0.8772563176895307 x 100 = -87.73%