87.5% is the change from 344 to 645
Calculation steps:
[( 645 - 344 ) ÷ 344] x 100 = 87.5%
Formula
Percentage change = [(645 - 344) / 344] x 100
Subtract the new number by the original number
645 - 344 = 301
301 ÷ 344 = 0.875
0.875 x 100 = 87.5%
Example