Reference line/Grid for a day in a week

[Anonymous]

Hi

I'm trying to add a grid/reference line for every Monday for my Gantt chart.

The chart is similar to the one show blew.  (Photo copied from Henric Cronström's post.Files for creation of a Gantt chart )

I would like either make the grid showing every Monday or add a reference line for every Monday.

Any idea how to achieve that?

Here's some sample data if you'd like to try.

Thanks!

sample data

Job ID	Time Started	Time Completed
1	August 16, 2015 at 9:54 AM	August 19, 2015 at 9:21 PM
2	August 20, 2015 at 5:55 PM	August 21, 2015 at 3:44 AM
3	September 8, 2015 at 4:49 PM	September 8, 2015 at 5:02 PM

[Digvijay_Singh]

It seems reference line do appear if aggregation expression used or hard coded date as shown in the image. One important change needed from last document is to have format of expression as 'Date'. Didn't see any post where multiple ref lines are added like it requires here.