98.75% is the change from 321 to 638
Calculation steps:
[( 638 - 321 ) ÷ 321] x 100 = 98.75%
Formula
Percentage change = [(638 - 321) / 321] x 100
Subtract the new number by the original number
638 - 321 = 317
317 ÷ 321 = 0.9875389408099688
0.9875389408099688 x 100 = 98.75%