27.49% is the change from 251 to 320
Calculation steps:
[( 320 - 251 ) ÷ 251] x 100 = 27.49%
Formula
Percentage change = [(320 - 251) / 251] x 100
Subtract the new number by the original number
320 - 251 = 69
69 ÷ 251 = 0.2749003984063745
0.2749003984063745 x 100 = 27.49%