Excel DateDif and Networkdays

[Costas]

DATEDIF is a hidden function in Excel.
http://www.exceltrick.com/formulas_macros/excel-datedif-function/

use (to diff excluding weekend) :

//http://www.mrexcel.com/forum/excel-questions/335055-datedif-excluding-weekends.html
=NETWORKDAYS(A1,B1)

#excel