-84.21% is the change from 399 to 63
Calculation steps:
[( 63 - 399 ) ÷ 399] x 100 = -84.21%
Formula
Percentage change = [(63 - 399) / 399] x 100
Subtract the new number by the original number
63 - 399 = -336
-336 ÷ 399 = -0.8421052631578947
-0.8421052631578947 x 100 = -84.21%