-29.57% is the change from 328 to 231
Calculation steps:
[( 231 - 328 ) ÷ 328] x 100 = -29.57%
Formula
Percentage change = [(231 - 328) / 328] x 100
Subtract the new number by the original number
231 - 328 = -97
-97 ÷ 328 = -0.29573170731707316
-0.29573170731707316 x 100 = -29.57%