-36.31% is the change from 639 to 407
Calculation steps:
[( 407 - 639 ) ÷ 639] x 100 = -36.31%
Formula
Percentage change = [(407 - 639) / 639] x 100
Subtract the new number by the original number
407 - 639 = -232
-232 ÷ 639 = -0.36306729264475746
-0.36306729264475746 x 100 = -36.31%