Splitting values in a pie chart

Question

I'm filling a report with a table that looks like this:

Code    |    Data
AAGU    |    AAGU = 41.43%; BCGS = 40.68%;
BCGS    |    BCGS = 41.43%; OTHER = 34.98%; XXX = 2%;

So my question is, how can I create a chart where each slice is one of the values that are separated by a semicolon?

This is what I tried so far,

1. Created a Matrix with the Rows section filled with the value of the Code column.
2. Inserted a Pie Chart in The Data section
3. In the Values section of the Pie Chart I used the following expression:

=Split(Fields!Data.Value, ";").Length

This is what I got:

Each Code row has a pie chart but only a single value: which is the entire data string. It was never splitted.

How can I achieve what I am looking for?