150.38% is the change from 399 to 999
Calculation steps:
[( 999 - 399 ) ÷ 399] x 100 = 150.38%
Formula
Percentage change = [(999 - 399) / 399] x 100
Subtract the new number by the original number
999 - 399 = 600
600 ÷ 399 = 1.5037593984962405
1.5037593984962405 x 100 = 150.38%