-87% is the change from 623 to 81
Calculation steps:
[( 81 - 623 ) ÷ 623] x 100 = -87%
Formula
Percentage change = [(81 - 623) / 623] x 100
Subtract the new number by the original number
81 - 623 = -542
-542 ÷ 623 = -0.869983948635634
-0.869983948635634 x 100 = -87%