-87.52% is the change from 665 to 83
Calculation steps:
[( 83 - 665 ) ÷ 665] x 100 = -87.52%
Formula
Percentage change = [(83 - 665) / 665] x 100
Subtract the new number by the original number
83 - 665 = -582
-582 ÷ 665 = -0.8751879699248121
-0.8751879699248121 x 100 = -87.52%