138.1% is the change from 399 to 950
Calculation steps:
[( 950 - 399 ) ÷ 399] x 100 = 138.1%
Formula
Percentage change = [(950 - 399) / 399] x 100
Subtract the new number by the original number
950 - 399 = 551
551 ÷ 399 = 1.380952380952381
1.380952380952381 x 100 = 138.1%