9.21% is the change from 391 to 427
Calculation steps:
[( 427 - 391 ) ÷ 391] x 100 = 9.21%
Formula
Percentage change = [(427 - 391) / 391] x 100
Subtract the new number by the original number
427 - 391 = 36
36 ÷ 391 = 0.09207161125319693
0.09207161125319693 x 100 = 9.21%