-98.5% is the change from 400 to 6
Calculation steps:
[( 6 - 400 ) ÷ 400] x 100 = -98.5%
Formula
Percentage change = [(6 - 400) / 400] x 100
Subtract the new number by the original number
6 - 400 = -394
-394 ÷ 400 = -0.985
-0.985 x 100 = -98.5%
Example