Allow me to expand on Andy's response.
To get a secondary axis, you display the format dialog of the series you want on the
secondary axis (at least one series must remain on the primary axis, so you need at
least two series). Do this by double clicking on the series. On the Axis tab of the
dialog, select Secondary. Generally Excel only provides the secondary Y axis. to get
the Secondary X axis now, choose Chart Options from the Chart menu, and on the Axes
tab, check the appropriate box under Secondary X Axis.
- Jon
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Jon Peltier, Microsoft Excel MVP
Peltier Technical Services
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http://PeltierTech.com/
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