-20.06% is the change from 319 to 255
Calculation steps:
[( 255 - 319 ) ÷ 319] x 100 = -20.06%
Formula
Percentage change = [(255 - 319) / 319] x 100
Subtract the new number by the original number
255 - 319 = -64
-64 ÷ 319 = -0.2006269592476489
-0.2006269592476489 x 100 = -20.06%