Hi,
To have 2 Y axes you need a minimum of 2 series of data. If you just want
dual axis labelling then the second set of data can be a repeat of the
first.
Otherwise create a chart with both series on the primary axis. Select one of
the series to move to the secondary y axis.
Format dialog > Series Options > Secondary axis.
Cheers
Andy
--
Andy Pope, Microsoft MVP - Excel
http://www.andypope.info