The formula below looks for a date selected in a combo box, then goes to another worksheet and returns the column letters of that date. The dates in the other worksheet is a rolling 21 week date range.

My question: Is there a way to display a "N/A" in the cell if the latest week's data is not updated yet? Right now, if there's missing data during the week selected, the cell shows a "0"... I tried to do a IF statement where that cell equals "0" but it kept giving me a circular error and it never worked anyways.

Any help is greatly appreciated.

=INDIRECT(ADDRESS($A313,COLUMN(INDIRECT(""&$E$4&"! "&G$4&"$3:"&G$4&"$509")),1,TRUE,"DMI"))