-87.58% is the change from 644 to 80
Calculation steps:
[( 80 - 644 ) ÷ 644] x 100 = -87.58%
Formula
Percentage change = [(80 - 644) / 644] x 100
Subtract the new number by the original number
80 - 644 = -564
-564 ÷ 644 = -0.8757763975155279
-0.8757763975155279 x 100 = -87.58%