Greetings Everyone,

I'm making a Excel 2013 spreadsheet that has formula in a column that auto enters a number 1-40 when something is entered to the left of that cell. There are 300 rows in the spreadsheet. I would like to make a drop down list in a column cell to the right that would delete that number in that cell from the drop down list.
For example cell C1 has 39, that 39 then is deleted from the drop down list. C2 has 22 in it, click on the drop down list cell and it shows 1-40 less 39 and 22.

Hope this makes sense. Thank you for looking.

ddevins