-26.88% is the change from 320 to 234
Calculation steps:
[( 234 - 320 ) ÷ 320] x 100 = -26.88%
Formula
Percentage change = [(234 - 320) / 320] x 100
Subtract the new number by the original number
234 - 320 = -86
-86 ÷ 320 = -0.26875
-0.26875 x 100 = -26.88%