51.5% is the change from 600 to 909
Calculation steps:
[( 909 - 600 ) ÷ 600] x 100 = 51.5%
Formula
Percentage change = [(909 - 600) / 600] x 100
Subtract the new number by the original number
909 - 600 = 309
309 ÷ 600 = 0.515
0.515 x 100 = 51.5%
Example