Comes down to whether you want the ratio of the current_AR to total_AR at all levels or the ratio of the detail level averaged at each level. The values would be the same at the detail level but change on the summary level. Most business users want the ratio of current_AR to total_AR at all levels.

Example :

Customer [A]

Current_AR, Total_AR

12, 30

10, 50

62, 100

Customer

Current_AR, Total_AR

90, 100

The formula you have used on each detail row is =sum(Fields!Current_AR.Value) / sum(Fields!Total_AR.Value)

So this would give :

A 12 30 40.00%

A 10 50 20.00%

A 62 150 62.00%

B 90 100 90.00%

If you add a group for customer using the same formula for each column would add the group footer rows:

A 84 180 46.67%

B 90 100 90.00%

Grouping to a tablix total would add:

Total 174 280 62.14%

You may not need to use the AVG function at all.

If you were to add the additional column RATIO into the dataset below then you could use the AVG function on these values but get a different returned value within the report.

SELECT *, Current_AR / Total_AR as Ratio

FROM dbo.SourceTable

RATIO

A 12 30 40.00%

A 10 50 20.00%

A 62 150 62.00%

B 90 100 90.00%

If you add a group for customer using the same formula for each column would add the group footer rows:

A 84 180 40.67% (avg of 40.00,20.00 and 62.00)

B 90 100 90.00%

Grouping to a tablix total would add:

Total 174 280 53.00% (avg of 40.00, 20.00, 62.00 and 90.00)

Fitz