-99.85% is the change from 669 to 1
Calculation steps:
[( 1 - 669 ) ÷ 669] x 100 = -99.85%
Formula
Percentage change = [(1 - 669) / 669] x 100
Subtract the new number by the original number
1 - 669 = -668
-668 ÷ 669 = -0.9985052316890882
-0.9985052316890882 x 100 = -99.85%