Pie Charts in Dynamics CRM only measure a single series. Pie Charts aggregate a single field's values within a given data set and give you the % for each available value in that data field.
For eg, I have a Contact record with an Option Set called Partner Status with 3 values:
1.) Gold
2.) Silver
3.) Bronze
The pie chart looks at all the Contacts in the view and aggregates the % of Gold vs. Silver vs. Bronze.
The way your form is configured, it ain't gonna work with an OOTB pie chart. Even pie charts that use multiple series (which, in my opinion makes them very confusing to read, unless the second series is a sub set of the 1st series (eg, Topic and Sub-Topic). Either way, measuring four numeric values in a single record for a pie chart isn't going to work (I'm assuming you'd like the pie chart to specifically reference the data in a single record, correct?)
Can you provide me more information? What do these data points reference?
Typically, when I see data like this:
Field1 = 10%
Field2 = 80%
Field3 = 5%
Field4 = 5%
You've essentially done the aggregation already, and there's no real need to visualize it...