List and Pie Chart Help

[Sela]

Hi, Sela here...

I'm new here, and a novice to Excel.
I have been looking for help on (I'm sure) this simple problem I have with Lists and charting.

I have set up a list like this;

Application Use Rank Percentage

Mozilla Firefox Browser hourly 1 35%
Outlook Express daily 2 25%
Notepad Text Editor weekly 3 20%
Irfanview Image Editor weekly 4 10%
Internet Explorer rarely 5 5%
Microsoft Word rarely 6 3%
Microsoft Excel rarely 7 2%

Currently my pie chart displays "all" correctly. I used the application and percentage (sum of 100%) columns for my chart data, but whenever I select (from the drop down list) to show just one of the applications, use, or rank, my chart does not show the correct slice percentage within the graph anymore - it's just a thin line out of 100%

What do I need to change or add, or how can I correct this?

I have uploaded a screen shot of the correct and incorrect examples.

Thanks for any help,
Sela