-6.78% is the change from 428 to 399
Calculation steps:
[( 399 - 428 ) ÷ 428] x 100 = -6.78%
Formula
Percentage change = [(399 - 428) / 428] x 100
Subtract the new number by the original number
399 - 428 = -29
-29 ÷ 428 = -0.06775700934579439
-0.06775700934579439 x 100 = -6.78%