64.19% is the change from 310 to 509
Calculation steps:
[( 509 - 310 ) ÷ 310] x 100 = 64.19%
Formula
Percentage change = [(509 - 310) / 310] x 100
Subtract the new number by the original number
509 - 310 = 199
199 ÷ 310 = 0.6419354838709678
0.6419354838709678 x 100 = 64.19%