-28.97% is the change from 321 to 228
Calculation steps:
[( 228 - 321 ) ÷ 321] x 100 = -28.97%
Formula
Percentage change = [(228 - 321) / 321] x 100
Subtract the new number by the original number
228 - 321 = -93
-93 ÷ 321 = -0.2897196261682243
-0.2897196261682243 x 100 = -28.97%