-87.3% is the change from 677 to 86
Calculation steps:
[( 86 - 677 ) ÷ 677] x 100 = -87.3%
Formula
Percentage change = [(86 - 677) / 677] x 100
Subtract the new number by the original number
86 - 677 = -591
-591 ÷ 677 = -0.8729689807976366
-0.8729689807976366 x 100 = -87.3%