-99.85% is the change from 668 to 1
Calculation steps:
[( 1 - 668 ) ÷ 668] x 100 = -99.85%
Formula
Percentage change = [(1 - 668) / 668] x 100
Subtract the new number by the original number
1 - 668 = -667
-667 ÷ 668 = -0.9985029940119761
-0.9985029940119761 x 100 = -99.85%