637.36% is the change from 91 to 671
Calculation steps:
[( 671 - 91 ) ÷ 91] x 100 = 637.36%
Formula
Percentage change = [(671 - 91) / 91] x 100
Subtract the new number by the original number
671 - 91 = 580
580 ÷ 91 = 6.373626373626373
6.373626373626373 x 100 = 637.36%