-17.97% is the change from 768 to 630
Calculation steps:
[( 630 - 768 ) ÷ 768] x 100 = -17.97%
Formula
Percentage change = [(630 - 768) / 768] x 100
Subtract the new number by the original number
630 - 768 = -138
-138 ÷ 768 = -0.1796875
-0.1796875 x 100 = -17.97%