102.61% is the change from 306 to 620
Calculation steps:
[( 620 - 306 ) ÷ 306] x 100 = 102.61%
Formula
Percentage change = [(620 - 306) / 306] x 100
Subtract the new number by the original number
620 - 306 = 314
314 ÷ 306 = 1.026143790849673
1.026143790849673 x 100 = 102.61%