665.15% is the change from 66 to 505
Calculation steps:
[( 505 - 66 ) ÷ 66] x 100 = 665.15%
Formula
Percentage change = [(505 - 66) / 66] x 100
Subtract the new number by the original number
505 - 66 = 439
439 ÷ 66 = 6.651515151515151
6.651515151515151 x 100 = 665.15%