Display Null Values As 0 On Line Chart

I have a report I'm writing and have got a problem that has stumped me.



The data the report is based in is in this format:



Date Type

1/1/08 A

1/3/08 B

3/1/08 C

3/5/08 B

3/10/08 A

3/12/08 C

3/20/08 A





Management wants a report showing a line chart that summarizes the data by Month and by Type. So, there are 2 series depending on the Type and data values are based on the count of each Type. So, in the example above the x-axis group would be month, the values would be count(Type) and there would be 2 series €“ Series 1. A, B and Series 2. C



I€™ve defined the x-axis to be Month(Fields!DateOccured.Value). However, they want the x-axis to show every month for the entire year not just what is in the database. So, I defined the x-axis to have a scale of 1 to 12 and the major interval is set to 1. This displays 1 through 12 on the x-axis.



The problem is when there is no data (null) for a particular month. Instead of showing 0, the line chart does not plot anything and the line is drawn to the next displayed point. So, for example on the data above the line chart would plot:

January

Series 1 €“ Qty. 2 Series 2 €“ Qty. 0

February

Null

March

Series 1 €“ Qty. 3 Series 2 €“ Qty. 2



The line chart would draw a line from January to March skipping February. I need to display the null values as 0 and not null indicating no occurrences for the month rather than no data present.



Thanks!