If you are a Customer - there should be something like 'Ideas Exchange" on a Customer Portal. If you are a Partner - the same on the Partners Portal.
Now that I think more about it - actually, you can do it!
- For the single Dimension or Expression, enter a multi-line label, something like the following:
and then allow a necessary amount of lines (in my example, 6) under "Wrap Header Lines" in the Presentation Tab.
This way, all the other labels will remain horizontal, and this one will appear vertical.
I am not sure whether we are the Customer or Partner. I have just created the account to learn many new things in QV.
As per your suggestion Multi Line Label will not work for me as the values are coming from the Field(Type of the field is Date). It is not a static(Hardcoded) value.
Do you have any other suggestions of doing it.