81.4% is the change from 344 to 624
Calculation steps:
[( 624 - 344 ) ÷ 344] x 100 = 81.4%
Formula
Percentage change = [(624 - 344) / 344] x 100
Subtract the new number by the original number
624 - 344 = 280
280 ÷ 344 = 0.813953488372093
0.813953488372093 x 100 = 81.4%