340.91% is the change from 66 to 291
Calculation steps:
[( 291 - 66 ) ÷ 66] x 100 = 340.91%
Formula
Percentage change = [(291 - 66) / 66] x 100
Subtract the new number by the original number
291 - 66 = 225
225 ÷ 66 = 3.409090909090909
3.409090909090909 x 100 = 340.91%