49.71% is the change from 348 to 521
Calculation steps:
[( 521 - 348 ) ÷ 348] x 100 = 49.71%
Formula
Percentage change = [(521 - 348) / 348] x 100
Subtract the new number by the original number
521 - 348 = 173
173 ÷ 348 = 0.49712643678160917
0.49712643678160917 x 100 = 49.71%