30.74% is the change from 257 to 336
Calculation steps:
[( 336 - 257 ) ÷ 257] x 100 = 30.74%
Formula
Percentage change = [(336 - 257) / 257] x 100
Subtract the new number by the original number
336 - 257 = 79
79 ÷ 257 = 0.30739299610894943
0.30739299610894943 x 100 = 30.74%