83.93% is the change from 280 to 515
Calculation steps:
[( 515 - 280 ) ÷ 280] x 100 = 83.93%
Formula
Percentage change = [(515 - 280) / 280] x 100
Subtract the new number by the original number
515 - 280 = 235
235 ÷ 280 = 0.8392857142857143
0.8392857142857143 x 100 = 83.93%