-18.57% is the change from 490 to 399
Calculation steps:
[( 399 - 490 ) ÷ 490] x 100 = -18.57%
Formula
Percentage change = [(399 - 490) / 490] x 100
Subtract the new number by the original number
399 - 490 = -91
-91 ÷ 490 = -0.18571428571428572
-0.18571428571428572 x 100 = -18.57%