George -
Next time don't use the built in custom chart type, because it'll do this whenever you add data.
Here's how to make your own combination chart.
Select the data, and make a standard chart that matches the type you'll use for half the series
(e.g., a column chart). Select a series you want to change, choose Chart Type from the Chart
menu, and choose the other type (a line). These won't change when you add more series. When you
add more series, Excel will guess what type you wanted, and odds are you'll have to change some
of them using Chart Type from the Chart menu, as above.
No need to trash your current chart, though. Just change the wrong series types as I've described.
- Jon
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Jon Peltier, Microsoft Excel MVP
Peltier Technical Services
Tutorials and Custom Solutions
http://PeltierTech.com/
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