-96.89% is the change from 644 to 20
Calculation steps:
[( 20 - 644 ) ÷ 644] x 100 = -96.89%
Formula
Percentage change = [(20 - 644) / 644] x 100
Subtract the new number by the original number
20 - 644 = -624
-624 ÷ 644 = -0.968944099378882
-0.968944099378882 x 100 = -96.89%