-42.9% is the change from 909 to 519
Calculation steps:
[( 519 - 909 ) ÷ 909] x 100 = -42.9%
Formula
Percentage change = [(519 - 909) / 909] x 100
Subtract the new number by the original number
519 - 909 = -390
-390 ÷ 909 = -0.429042904290429
-0.429042904290429 x 100 = -42.9%
Example