Dynamic drop down list

Hello

I have to create a dynamic drop down list that takes the values from another excel file. The problem is that the values are the names of the columns and that the number of the columns change from month to month.

Any ideas how I can do this?
Thank you!

You can't create a drop down with the values from another workbook directly, you will have to get them into your target workbook as data first, construct the dynamic drop down there, then use it.

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Let's say the workbook with the values to import is Book1.xls, and the sheet is Sheet1, and the row with the values is row 1 starting at A1, then B1, then C1, etc.

In the workbook where you are building the dynamic drop down, put this formula in A1, then copy down as far as you need to go to accommodate the expanding values (resist the urge to go down forever, make a sold range decision here, 100 rows?)

=IF(INDEX([Book1.xls]Sheet1!$1:$1, ROW(A1))=0, "", INDEX([Book1.xls]Sheet1!$1:$1, ROW(A1)))

That should cause the text values to appear and the cells will go blank when the values are blank in the source document.

Then in the new workbook, use this formula to create your dynamic named range, Insert > Name > Define > MyList
Refers To: =OFFSET($A$1,0,0,MATCH("*",$A:$A,-1),1)


Then in the cells where you want to use this new drop down, Data > Validation > List > Source: MyList