ALV GRID display with Average and subtotals.

Hi Team,

i have a requirement like display the ALV Grid report with calculate the Average and Sub totals based on Customer(KUNNR).

Kunnr Amount

100001 100

200

300

400

100002 200

400

Need to be output as follows:

Kunnr Amount

100001 100

200

300

400

Avearge 250

Sub total 1000

100002 200

400

Avearge 300

Sub total 600

This is the requirement . Could you please suggest me it is possible to do it.If yes then please suggest me how to do this.

Thanks in Advance.

Puneet.