-98.91% is the change from 644 to 7
Calculation steps:
[( 7 - 644 ) ÷ 644] x 100 = -98.91%
Formula
Percentage change = [(7 - 644) / 644] x 100
Subtract the new number by the original number
7 - 644 = -637
-637 ÷ 644 = -0.9891304347826086
-0.9891304347826086 x 100 = -98.91%