49.28% is the change from 207 to 309
Calculation steps:
[( 309 - 207 ) ÷ 207] x 100 = 49.28%
Formula
Percentage change = [(309 - 207) / 207] x 100
Subtract the new number by the original number
309 - 207 = 102
102 ÷ 207 = 0.4927536231884058
0.4927536231884058 x 100 = 49.28%