-7.5% is the change from 680 to 629
Calculation steps:
[( 629 - 680 ) ÷ 680] x 100 = -7.5%
Formula
Percentage change = [(629 - 680) / 680] x 100
Subtract the new number by the original number
629 - 680 = -51
-51 ÷ 680 = -0.075
-0.075 x 100 = -7.5%
Example