Microsoft Excel's Data Validation tool lets you add a drop-down list to a cell based on existing data in a column. However, how this works depends on whether the source data is part of a formatted ...

So, select any cell in your formatted Excel table, and in the Insert Tab on the ribbon, click the top half of the split ...

Microsoft's spreadsheet program can do way more than you might realize. These are the hacks and tricks you need to know.