-56% is the change from 909 to 400
Calculation steps:
[( 400 - 909 ) ÷ 909] x 100 = -56%
Formula
Percentage change = [(400 - 909) / 909] x 100
Subtract the new number by the original number
400 - 909 = -509
-509 ÷ 909 = -0.55995599559956
-0.55995599559956 x 100 = -56%