Exporting a report as an XLSX not an XLS format in Excel

Is there a way to export reports as an XLSX not XLS as this is an old format and has size limitation which makes it impossible to produce weekly and monthly reports if there are over 65000 lines. As the xls is an old format will newer versions of Solarwinds make this possible.

The version I am using is 6.3.0.1

Thanks

Lee