23.11% is the change from 251 to 309
Calculation steps:
[( 309 - 251 ) ÷ 251] x 100 = 23.11%
Formula
Percentage change = [(309 - 251) / 251] x 100
Subtract the new number by the original number
309 - 251 = 58
58 ÷ 251 = 0.23107569721115537
0.23107569721115537 x 100 = 23.11%