That arrow (could point up or down) indicates that the column has been sorted
either Ascending or Descending using the AutoFilter.

HTH,
Elkar


"EllenOJD" wrote:

In Excel 2007, one of our users noticed a small, black arrow on the filter
button in her spreadsheet. It appears to the right of the filter or standard
arrow on the button and it's a skinny black arrow pointing up. What is this
and what does it mean/do?
--
EllenOJD