59.75% is the change from 400 to 639
Calculation steps:
[( 639 - 400 ) ÷ 400] x 100 = 59.75%
Formula
Percentage change = [(639 - 400) / 400] x 100
Subtract the new number by the original number
639 - 400 = 239
239 ÷ 400 = 0.5975
0.5975 x 100 = 59.75%