-87.73% is the change from 644 to 79
Calculation steps:
[( 79 - 644 ) ÷ 644] x 100 = -87.73%
Formula
Percentage change = [(79 - 644) / 644] x 100
Subtract the new number by the original number
79 - 644 = -565
-565 ÷ 644 = -0.8773291925465838
-0.8773291925465838 x 100 = -87.73%