-34.83% is the change from 979 to 638
Calculation steps:
[( 638 - 979 ) ÷ 979] x 100 = -34.83%
Formula
Percentage change = [(638 - 979) / 979] x 100
Subtract the new number by the original number
638 - 979 = -341
-341 ÷ 979 = -0.34831460674157305
-0.34831460674157305 x 100 = -34.83%