-6.31% is the change from 666 to 624
Calculation steps:
[( 624 - 666 ) ÷ 666] x 100 = -6.31%
Formula
Percentage change = [(624 - 666) / 666] x 100
Subtract the new number by the original number
624 - 666 = -42
-42 ÷ 666 = -0.06306306306306306
-0.06306306306306306 x 100 = -6.31%