65.37% is the change from 309 to 511
Calculation steps:
[( 511 - 309 ) ÷ 309] x 100 = 65.37%
Formula
Percentage change = [(511 - 309) / 309] x 100
Subtract the new number by the original number
511 - 309 = 202
202 ÷ 309 = 0.6537216828478964
0.6537216828478964 x 100 = 65.37%