How to position the xaxis label on right side of plot's x-axis

I have a number of scatter plots stacked vertically one on top of another.

if I show the xaxis label for each plot then it looks like the plot’s xaxis label is the title of the next plot because of where it is being placed.

How can I position all the xaxis labels on the far right of each xaxis?

I figured it out… I can use annotations to do what I need as illustrated here: