@Karen Phillips the only two native export options are Word and PDF. You would need to export to Word and then copy the table into Excel if you need it in that format. Since the exports were built for the sake of documentation, the standard documentation platforms are the only targets.
If you have the Table Filter and Charts for Confluence app installed (this add-on is developed by our company), you may use the following workaround: wrap the Decision Report macro in the Table Filter macro and use the latter to export your decisions in csv format. Hope it helps.
