-86.56% is the change from 677 to 91
Calculation steps:
[( 91 - 677 ) ÷ 677] x 100 = -86.56%
Formula
Percentage change = [(91 - 677) / 677] x 100
Subtract the new number by the original number
91 - 677 = -586
-586 ÷ 677 = -0.8655834564254062
-0.8655834564254062 x 100 = -86.56%