-91.43% is the change from 315 to 27
Calculation steps:
[( 27 - 315 ) ÷ 315] x 100 = -91.43%
Formula
Percentage change = [(27 - 315) / 315] x 100
Subtract the new number by the original number
27 - 315 = -288
-288 ÷ 315 = -0.9142857142857143
-0.9142857142857143 x 100 = -91.43%