-90.38% is the change from 842 to 81
Calculation steps:
[( 81 - 842 ) ÷ 842] x 100 = -90.38%
Formula
Percentage change = [(81 - 842) / 842] x 100
Subtract the new number by the original number
81 - 842 = -761
-761 ÷ 842 = -0.9038004750593824
-0.9038004750593824 x 100 = -90.38%