It is not possible to specify the NumberFormat (even using the ExcelStyle). We added this as a feature request. However, we cannot give a time frame as of when (or if) this feature will be added.
As a workaround, you would need to set the FormatSpecifier of the column to 0.000 and set the exportation mode to “Display Text”.
Imported from legacy forums. Posted by CharlesB (had 382 views)