-23.63% is the change from 639 to 488
Calculation steps:
[( 488 - 639 ) ÷ 639] x 100 = -23.63%
Formula
Percentage change = [(488 - 639) / 639] x 100
Subtract the new number by the original number
488 - 639 = -151
-151 ÷ 639 = -0.23630672926447574
-0.23630672926447574 x 100 = -23.63%