32.47% is the change from 231 to 306
Calculation steps:
[( 306 - 231 ) ÷ 231] x 100 = 32.47%
Formula
Percentage change = [(306 - 231) / 231] x 100
Subtract the new number by the original number
306 - 231 = 75
75 ÷ 231 = 0.3246753246753247
0.3246753246753247 x 100 = 32.47%