-86.7% is the change from 684 to 91
Calculation steps:
[( 91 - 684 ) ÷ 684] x 100 = -86.7%
Formula
Percentage change = [(91 - 684) / 684] x 100
Subtract the new number by the original number
91 - 684 = -593
-593 ÷ 684 = -0.8669590643274854
-0.8669590643274854 x 100 = -86.7%