-85.4% is the change from 685 to 100
Calculation steps:
[( 100 - 685 ) ÷ 685] x 100 = -85.4%
Formula
Percentage change = [(100 - 685) / 685] x 100
Subtract the new number by the original number
100 - 685 = -585
-585 ÷ 685 = -0.8540145985401459
-0.8540145985401459 x 100 = -85.4%