34.38% is the change from 256 to 344
Calculation steps:
[( 344 - 256 ) ÷ 256] x 100 = 34.38%
Formula
Percentage change = [(344 - 256) / 256] x 100
Subtract the new number by the original number
344 - 256 = 88
88 ÷ 256 = 0.34375
0.34375 x 100 = 34.38%