-86.5% is the change from 585 to 79
Calculation steps:
[( 79 - 585 ) ÷ 585] x 100 = -86.5%
Formula
Percentage change = [(79 - 585) / 585] x 100
Subtract the new number by the original number
79 - 585 = -506
-506 ÷ 585 = -0.864957264957265
-0.864957264957265 x 100 = -86.5%