659.09% is the change from 66 to 501
Calculation steps:
[( 501 - 66 ) ÷ 66] x 100 = 659.09%
Formula
Percentage change = [(501 - 66) / 66] x 100
Subtract the new number by the original number
501 - 66 = 435
435 ÷ 66 = 6.590909090909091
6.590909090909091 x 100 = 659.09%