-90.32% is the change from 857 to 83
Calculation steps:
[( 83 - 857 ) ÷ 857] x 100 = -90.32%
Formula
Percentage change = [(83 - 857) / 857] x 100
Subtract the new number by the original number
83 - 857 = -774
-774 ÷ 857 = -0.9031505250875146
-0.9031505250875146 x 100 = -90.32%