-34.32% is the change from 979 to 643
Calculation steps:
[( 643 - 979 ) ÷ 979] x 100 = -34.32%
Formula
Percentage change = [(643 - 979) / 979] x 100
Subtract the new number by the original number
643 - 979 = -336
-336 ÷ 979 = -0.3432073544433095
-0.3432073544433095 x 100 = -34.32%