291.76% is the change from 255 to 999
Calculation steps:
[( 999 - 255 ) ÷ 255] x 100 = 291.76%
Formula
Percentage change = [(999 - 255) / 255] x 100
Subtract the new number by the original number
999 - 255 = 744
744 ÷ 255 = 2.9176470588235293
2.9176470588235293 x 100 = 291.76%