-99.07% is the change from 644 to 6
Calculation steps:
[( 6 - 644 ) ÷ 644] x 100 = -99.07%
Formula
Percentage change = [(6 - 644) / 644] x 100
Subtract the new number by the original number
6 - 644 = -638
-638 ÷ 644 = -0.9906832298136646
-0.9906832298136646 x 100 = -99.07%