-56.09% is the change from 911 to 400
Calculation steps:
[( 400 - 911 ) ÷ 911] x 100 = -56.09%
Formula
Percentage change = [(400 - 911) / 911] x 100
Subtract the new number by the original number
400 - 911 = -511
-511 ÷ 911 = -0.5609220636663008
-0.5609220636663008 x 100 = -56.09%