-79.31% is the change from 638 to 132
Calculation steps:
[( 132 - 638 ) ÷ 638] x 100 = -79.31%
Formula
Percentage change = [(132 - 638) / 638] x 100
Subtract the new number by the original number
132 - 638 = -506
-506 ÷ 638 = -0.7931034482758621
-0.7931034482758621 x 100 = -79.31%