Thanks. That helps. I can work with the numbers since I always have the same amount of month on the x axes.

I noticed that it is also possible to use for example 5,5 as value to set the line between tick marks.

When the chart category axis is in categorical mode, the actual X values of the categories are 0, 1, 2 etc. That is a const line displayed for the first group must have a value of 0. (assuming you want to display vertical constant lines for specific categories). That is why mapping a certain yyMM value to a category number is not possible via expressions, but is possible with custom code. You can contact Nevron Consulting at contacts@nevronconsulting.com, if you would like them to do this for you.

Best Regards,
Nevron Support Team

Hello,

My primary X Axes is grouped by following statement: =FORMAT(Fields!ESA_IVRProcessEnd,"yyMM").

How can I set a const line on a specific yyMM value? Is that possible?

Thank you for your help!