-6.33% is the change from 663 to 621
Calculation steps:
[( 621 - 663 ) ÷ 663] x 100 = -6.33%
Formula
Percentage change = [(621 - 663) / 663] x 100
Subtract the new number by the original number
621 - 663 = -42
-42 ÷ 663 = -0.06334841628959276
-0.06334841628959276 x 100 = -6.33%