Place Text box between X axis and bottom border of chart

[TimTDP]

In Excel 2010 I need to place a text box between the X axis and the bottom border of a chart.
How can increase the white space between the X axis and the bottom border to allow me to do this?

 

[Derek Brown]

If I needed to do this on a chart where the Y-axis started at zero, I would set a negative minimum value for the Y-axis. The value would be such that the zero would still be shown. I would then format the Y-axis numbers as Custom:
#,##0;[White]-#,##0
This would raise the X-axis.