-9.09% is the change from 429 to 390
Calculation steps:
[( 390 - 429 ) ÷ 429] x 100 = -9.09%
Formula
Percentage change = [(390 - 429) / 429] x 100
Subtract the new number by the original number
390 - 429 = -39
-39 ÷ 429 = -0.09090909090909091
-0.09090909090909091 x 100 = -9.09%