How to add line number to a BOM template

How to format BOM template column to include line # (line number). Unable to add Line # using the Column=Line Number Format in a BOM Template

Starting in Version: 18.0
Up to Version: Current

Solution Details

The Column declaration in the Excel template is replaced by the ColumnName string, with each row below being populated by that column value for each BOM Item.

Columns are used in the format:

Column=ColumnName

An example would be Column=Designator. 
In order to include Line #'s from the Active BOM  in a BOM template, the format is Column=Line #


Here is additional documentation that may be of interest:
https://www.altium.com/documentation/altium-designer/bom-configuration-in-the-report-manager-ad#!mapping-design-data-into-the-bom

Here's a list of pre-defined special strings:
https://www.altium.com/documentation/altium-designer/pcb-obj-stringstring-ad#!pcb-predefined-special-strings

Here's information on User-Defined project parameters:
https://www.altium.com/documentation/altium-designer/workspacemanager-dlg-projectpropertiesdialog-pagecontrol-main-parametersproject-options-parameters-ad

If you want to turn on/off columns, it can be done in the Properties panel.