Expression "Top values"

[#1]

Hello again,

i have a small problem i dont know how to solve. Hope somebody can .

I have a chart with values:

Grupa VRD - Nr. Items by customer

Grupa VRD is a fix value (from 1 - 12) and is something like "Item declaration"

Items by customer is this formula:

count({$<Datum_fakture={">=$(Datum od1) <=$(Datum do1)"}>}DISTINCT ITEMID)/count({$<Datum_fakture={">=$(Datum od1) <=$(Datum do1)"}>}DISTINCT CUSTACCOUNT)

Count Nr. of old ITEMS and divide through nr. of Customers in the selected period.

The chart shows me for every Grupa VRD the wanted number, after selecting the Filter "Salesmen"

Ex.: Salesmen Nr. 004

1 - 2.3

2 - 2.5

3 - 1.5

etc...

Problem:

I need to add a column which shows me the Nr.(Item by customers) as an average by the TOP 3 Salesmen(TOP for GRUPA VRD) that is NOT changeable by filters(fix calculation).

Like this:

Filer: Salesmen Nr. 004

Grupa VRD - nr Items by customer - Average of Top 3

1 - 2.3 - 4.5

2 - 2.5 - 3.0

3 - 1.5 - 6.0

Filer: Salesmen Nr. 006

Grupa VRD - nr Items by customer - Average of Top 3

1 - 2.0 - 4.5

2 - 2.0 - 3.0

3 - 3.0 - 6.0

Can anybody help me?

Thank you in advance.