-16.92% is the change from 390 to 324
Calculation steps:
[( 324 - 390 ) ÷ 390] x 100 = -16.92%
Formula
Percentage change = [(324 - 390) / 390] x 100
Subtract the new number by the original number
324 - 390 = -66
-66 ÷ 390 = -0.16923076923076924
-0.16923076923076924 x 100 = -16.92%