Multi Field calculation

[Nandakishore]

Hi ,

Can someone help me with calculation as mentioned below : 

	P1	P2	P3	P4	P5
A1	1	3	5	7	9
A2	2	4	6	8	10
A3	3	10	21	36	55

Solution has to auto calculate values in bold for each closing period . For example : 

P2A3=

P1A3+P2A1+P2A2

Thankyou

[TimN]

One way