3.5% is the change from 343 to 355
Calculation steps:
[( 355 - 343 ) ÷ 343] x 100 = 3.5%
Formula
Percentage change = [(355 - 343) / 343] x 100
Subtract the new number by the original number
355 - 343 = 12
12 ÷ 343 = 0.03498542274052478
0.03498542274052478 x 100 = 3.5%