Help with Function Procedure?

[Lalo2DaG]

I download a report every day. This report tells me how olda certain product will be by a future date. For my purposes, I have to then adda column and do a quick calculation. My calculation is as follows: Future date –Todays date = number of days. <o></o>
For example, the product future date is 10/1/2017 and todaysdate is 11/30/2016. 10/1/2017 – 11/30/2016= 305 days.<o></o>
I have been trying to find a way to write code to do thisfor me, preferably without having to add an extra column. I think it should be a functionprocedure. The column on the excel sheetis “AF”. I hope I made my question clearand not overly confusing. But any help would be greatly appreciated. Thank you.<o></o>

 

[BQardi]

If you don't want an extra column, how would you like this information to be presented to you?

 

[Lalo2DaG]

Preferably if the existing column is overwritten.

 

[BQardi]

something like this:

Sub NumDaysToFutureDate()
Dim rng As Range, cell As Range, FutureDate As Variant
Application.ScreenUpdating = False
Set rng = Range("AF1", Cells(Rows.Count, "AF").End(xlUp))
For Each cell In rng
    On Error Resume Next
    FutureDate = CDate(cell.Value)
    On Error GoTo 0
    If FutureDate > Date And VarType(FutureDate) = vbDate Then cell.Value = FutureDate - Date
Next cell
rng.NumberFormat = "0"
End Sub