-90.5% is the change from 842 to 80
Calculation steps:
[( 80 - 842 ) ÷ 842] x 100 = -90.5%
Formula
Percentage change = [(80 - 842) / 842] x 100
Subtract the new number by the original number
80 - 842 = -762
-762 ÷ 842 = -0.9049881235154394
-0.9049881235154394 x 100 = -90.5%