inverting a chart
 

I have created quite complex chart in vba where I plot probability
values on the y axis and data along the x axis. I would like to provide
an option to plot the probability on the x axis and data on the y axis.
Is there an easy way to flip the axes around?
At the moment, I am stuck on
ActiveChart.SeriesCollection(2).XValues = "=Data!R2C60:R24C60"
ActiveChart.SeriesCollection(2).Values = "=Data!R2C55:R24C55"
where it plots the probability values on the y axis. How do I change
this to plot on the x axis?

Thanks
Chris