50% is the change from 230 to 345
Calculation steps:
[( 345 - 230 ) ÷ 230] x 100 = 50%
Formula
Percentage change = [(345 - 230) / 230] x 100
Subtract the new number by the original number
345 - 230 = 115
115 ÷ 230 = 0.5
0.5 x 100 = 50%
Example