819.7% is the change from 66 to 607
Calculation steps:
[( 607 - 66 ) ÷ 66] x 100 = 819.7%
Formula
Percentage change = [(607 - 66) / 66] x 100
Subtract the new number by the original number
607 - 66 = 541
541 ÷ 66 = 8.196969696969697
8.196969696969697 x 100 = 819.7%