-4.55% is the change from 660 to 630
Calculation steps:
[( 630 - 660 ) ÷ 660] x 100 = -4.55%
Formula
Percentage change = [(630 - 660) / 660] x 100
Subtract the new number by the original number
630 - 660 = -30
-30 ÷ 660 = -0.045454545454545456
-0.045454545454545456 x 100 = -4.55%