-7.42% is the change from 310 to 287
Calculation steps:
[( 287 - 310 ) ÷ 310] x 100 = -7.42%
Formula
Percentage change = [(287 - 310) / 310] x 100
Subtract the new number by the original number
287 - 310 = -23
-23 ÷ 310 = -0.07419354838709677
-0.07419354838709677 x 100 = -7.42%