Weekly Rolling Average 2 weeks before and after

[tmears]

I am at a total lose with this one.  I have been asked to produce 4 week weekly moving average of events covering two weeks before and two weeks after the event date.  I just keep going around in circles!!!  do i need to create a summary table?

Any help or pointers would be greatly appriciated

Event  Date	salesorderid	week number
15/04/2011 00:00	106feb2e-88e9-e811-a8cb-00224801a6a4	16
20/04/2011 00:00	c169f328-88e9-e811-a8cb-00224801a6a4	17
17/06/2011 00:00	146feb2e-88e9-e811-a8cb-00224801a6a4	25
20/07/2011 00:00	5679eb2e-88e9-e811-a8cb-00224801a6a4	30
14/09/2011 00:00	0f8ceb2e-88e9-e811-a8cb-00224801a6a4	38
06/10/2011 00:00	4c7eeb2e-88e9-e811-a8cb-00224801a6a4	41
14/10/2011 00:00	0a6ceb2e-88e9-e811-a8cb-00224801a6a4	42
17/11/2011 00:00	1a6feb2e-88e9-e811-a8cb-00224801a6a4	47
22/11/2011 00:00	0f73eb2e-88e9-e811-a8cb-00224801a6a4	48
16/12/2011 00:00	bf6deb2e-88e9-e811-a8cb-00224801a6a4	51
28/03/2012 00:00	288aeb2e-88e9-e811-a8cb-00224801a6a4	13
29/03/2012 00:00	f16feb2e-88e9-e811-a8cb-00224801a6a4	13
13/04/2012 00:00	fc7eeb2e-88e9-e811-a8cb-00224801a6a4	15
21/05/2012 00:00	0774eb2e-88e9-e811-a8cb-00224801a6a4	21
25/06/2012 00:00	ad6deb2e-88e9-e811-a8cb-00224801a6a4	26
09/07/2012 00:00	c56deb2e-88e9-e811-a8cb-00224801a6a4	28
14/07/2012 00:00	db6deb2e-88e9-e811-a8cb-00224801a6a4	28

[lbendlin · Accepted solution]

There are many ways of doing this, here is one example