-8.93% is the change from 336 to 306
Calculation steps:
[( 306 - 336 ) ÷ 336] x 100 = -8.93%
Formula
Percentage change = [(306 - 336) / 336] x 100
Subtract the new number by the original number
306 - 336 = -30
-30 ÷ 336 = -0.08928571428571429
-0.08928571428571429 x 100 = -8.93%