674.42% is the change from 86 to 666
Calculation steps:
[( 666 - 86 ) ÷ 86] x 100 = 674.42%
Formula
Percentage change = [(666 - 86) / 86] x 100
Subtract the new number by the original number
666 - 86 = 580
580 ÷ 86 = 6.744186046511628
6.744186046511628 x 100 = 674.42%