-71.37% is the change from 255 to 73
Calculation steps:
[( 73 - 255 ) ÷ 255] x 100 = -71.37%
Formula
Percentage change = [(73 - 255) / 255] x 100
Subtract the new number by the original number
73 - 255 = -182
-182 ÷ 255 = -0.7137254901960784
-0.7137254901960784 x 100 = -71.37%