0.5% is the change from 399 to 401
Calculation steps:
[( 401 - 399 ) ÷ 399] x 100 = 0.5%
Formula
Percentage change = [(401 - 399) / 399] x 100
Subtract the new number by the original number
401 - 399 = 2
2 ÷ 399 = 0.005012531328320802
0.005012531328320802 x 100 = 0.5%