-2.52% is the change from 318 to 310
Calculation steps:
[( 310 - 318 ) ÷ 318] x 100 = -2.52%
Formula
Percentage change = [(310 - 318) / 318] x 100
Subtract the new number by the original number
310 - 318 = -8
-8 ÷ 318 = -0.025157232704402517
-0.025157232704402517 x 100 = -2.52%