69.26% is the change from 309 to 523
Calculation steps:
[( 523 - 309 ) ÷ 309] x 100 = 69.26%
Formula
Percentage change = [(523 - 309) / 309] x 100
Subtract the new number by the original number
523 - 309 = 214
214 ÷ 309 = 0.6925566343042071
0.6925566343042071 x 100 = 69.26%