-21.97% is the change from 396 to 309
Calculation steps:
[( 309 - 396 ) ÷ 396] x 100 = -21.97%
Formula
Percentage change = [(309 - 396) / 396] x 100
Subtract the new number by the original number
309 - 396 = -87
-87 ÷ 396 = -0.2196969696969697
-0.2196969696969697 x 100 = -21.97%