3061.9% is the change from 21 to 664
Calculation steps:
[( 664 - 21 ) ÷ 21] x 100 = 3061.9%
Formula
Percentage change = [(664 - 21) / 21] x 100
Subtract the new number by the original number
664 - 21 = 643
643 ÷ 21 = 30.61904761904762
30.61904761904762 x 100 = 3061.9%