-9.73% is the change from 339 to 306
Calculation steps:
[( 306 - 339 ) ÷ 339] x 100 = -9.73%
Formula
Percentage change = [(306 - 339) / 339] x 100
Subtract the new number by the original number
306 - 339 = -33
-33 ÷ 339 = -0.09734513274336283
-0.09734513274336283 x 100 = -9.73%