"Dynamic" pie chars?

[Markstar]

Hi,
so I'm facing what I think is a common problem, but despite using Google I could not figure how to create the pie charts that I want.

What I want is a usual expense sheet with 3 columns: item, category, value:

Item    Type    Value
Apple    Fruit    1
Banana    Fruit    2
Kiwi    Fruit    3
Banana    Fruit    2
Vanilla    Flavor    7
Apple    Flavor    2
Soda    Misc    5
Broom    Misc    30
Soda    Misc    5
Cumin    Flavor    42

Now I want "dynamic" pie charts, depending on the number of categories. In the attached example, I have 3 categories, so I would want 4 pie charts:

• 1 overview chart, comparing the different categories (so in the example the pie chart shows 3 sections: Fruit, Flavor, Misc)
• 3 charts for each category, showing the items but still combining them if applicable (e.g. for Misc, the pie chart would have only 2 segments; Soda and Broom, split 25%-75%)

I have solve the first one, though I think it is not very elegant, by having an extra cell for each category and using SUMIF() to add the corresponding values.

But I have no idea how to get the others to work when it is unknown what is going to be entered under "Item". Do I have to use helper cells or is there a way to accomplish this in the pie chart wizard directly? I've tried for a while but can't get it to work, so any input would be greatly appreciated!

Thank you in advance for you help!