-98.95% is the change from 666 to 7
Calculation steps:
[( 7 - 666 ) ÷ 666] x 100 = -98.95%
Formula
Percentage change = [(7 - 666) / 666] x 100
Subtract the new number by the original number
7 - 666 = -659
-659 ÷ 666 = -0.9894894894894894
-0.9894894894894894 x 100 = -98.95%