How can I set the label rotation (specifically x-axis labels) when using Custom XML for a chart?
I know how to do it in the Chart Attributes:

But I have a few charts where I needed to use the Custom XML option to achieve certain customization requirements and I can't see a place to set it in the XML code.
What I currently have (in terms of x-axis labels):

What I want the labels to look like (Rotated 90 degrees):

Thank you!