-45% is the change from 580 to 319
Calculation steps:
[( 319 - 580 ) ÷ 580] x 100 = -45%
Formula
Percentage change = [(319 - 580) / 580] x 100
Subtract the new number by the original number
319 - 580 = -261
-261 ÷ 580 = -0.45
-0.45 x 100 = -45%
Example