631.87% is the change from 91 to 666
Calculation steps:
[( 666 - 91 ) ÷ 91] x 100 = 631.87%
Formula
Percentage change = [(666 - 91) / 91] x 100
Subtract the new number by the original number
666 - 91 = 575
575 ÷ 91 = 6.318681318681318
6.318681318681318 x 100 = 631.87%