-31.96% is the change from 316 to 215
Calculation steps:
[( 215 - 316 ) ÷ 316] x 100 = -31.96%
Formula
Percentage change = [(215 - 316) / 316] x 100
Subtract the new number by the original number
215 - 316 = -101
-101 ÷ 316 = -0.31962025316455694
-0.31962025316455694 x 100 = -31.96%