38.1% is the change from 231 to 319
Calculation steps:
[( 319 - 231 ) ÷ 231] x 100 = 38.1%
Formula
Percentage change = [(319 - 231) / 231] x 100
Subtract the new number by the original number
319 - 231 = 88
88 ÷ 231 = 0.38095238095238093
0.38095238095238093 x 100 = 38.1%