-0.31% is the change from 318 to 317
Calculation steps:
[( 317 - 318 ) ÷ 318] x 100 = -0.31%
Formula
Percentage change = [(317 - 318) / 318] x 100
Subtract the new number by the original number
317 - 318 = -1
-1 ÷ 318 = -0.0031446540880503146
-0.0031446540880503146 x 100 = -0.31%