49.55% is the change from 555 to 830
Calculation steps:
[( 830 - 555 ) ÷ 555] x 100 = 49.55%
Formula
Percentage change = [(830 - 555) / 555] x 100
Subtract the new number by the original number
830 - 555 = 275
275 ÷ 555 = 0.4954954954954955
0.4954954954954955 x 100 = 49.55%