-45.5% is the change from 400 to 218
Calculation steps:
[( 218 - 400 ) ÷ 400] x 100 = -45.5%
Formula
Percentage change = [(218 - 400) / 400] x 100
Subtract the new number by the original number
218 - 400 = -182
-182 ÷ 400 = -0.455
-0.455 x 100 = -45.5%