-86.81% is the change from 690 to 91
Calculation steps:
[( 91 - 690 ) ÷ 690] x 100 = -86.81%
Formula
Percentage change = [(91 - 690) / 690] x 100
Subtract the new number by the original number
91 - 690 = -599
-599 ÷ 690 = -0.8681159420289855
-0.8681159420289855 x 100 = -86.81%