Plotting order of Column graphs

How do you change the order that bars are plotted on my Column graph?

The two graphs in this example are identical except that the plotting order was reversed.

To change the plotting order of the data sets on a graph:

Click the Rotate/Flip button in the Change section of the Prism toolbar to reverse the  left-to-right order of data sets on a graph.

To fine tune the left-to-right order, go to the Data Sets on Graph tab of the Format Graph dialog.