-30.97% is the change from 310 to 214
Calculation steps:
[( 214 - 310 ) ÷ 310] x 100 = -30.97%
Formula
Percentage change = [(214 - 310) / 310] x 100
Subtract the new number by the original number
214 - 310 = -96
-96 ÷ 310 = -0.3096774193548387
-0.3096774193548387 x 100 = -30.97%