196.43% is the change from 280 to 830
Calculation steps:
[( 830 - 280 ) ÷ 280] x 100 = 196.43%
Formula
Percentage change = [(830 - 280) / 280] x 100
Subtract the new number by the original number
830 - 280 = 550
550 ÷ 280 = 1.9642857142857142
1.9642857142857142 x 100 = 196.43%