-87.67% is the change from 657 to 81
Calculation steps:
[( 81 - 657 ) ÷ 657] x 100 = -87.67%
Formula
Percentage change = [(81 - 657) / 657] x 100
Subtract the new number by the original number
81 - 657 = -576
-576 ÷ 657 = -0.8767123287671232
-0.8767123287671232 x 100 = -87.67%