-7.35% is the change from 680 to 630
Calculation steps:
[( 630 - 680 ) ÷ 680] x 100 = -7.35%
Formula
Percentage change = [(630 - 680) / 680] x 100
Subtract the new number by the original number
630 - 680 = -50
-50 ÷ 680 = -0.07352941176470588
-0.07352941176470588 x 100 = -7.35%