-36.39% is the change from 643 to 409
Calculation steps:
[( 409 - 643 ) ÷ 643] x 100 = -36.39%
Formula
Percentage change = [(409 - 643) / 643] x 100
Subtract the new number by the original number
409 - 643 = -234
-234 ÷ 643 = -0.36391912908242613
-0.36391912908242613 x 100 = -36.39%