-87.76% is the change from 662 to 81
Calculation steps:
[( 81 - 662 ) ÷ 662] x 100 = -87.76%
Formula
Percentage change = [(81 - 662) / 662] x 100
Subtract the new number by the original number
81 - 662 = -581
-581 ÷ 662 = -0.877643504531722
-0.877643504531722 x 100 = -87.76%