Only customers appearing in the same period. How?

[#1]

Hi.

I'm moving my very first steps with Qlik.
I have a table with these info:

- Transaction date (from jan 2013 till mar 2014).

- Customer ID

- Store ID

- Value

My draft dashboard allows to select months and/or weeks to show comparison Values for 2013 and 2014.

How can I show comparison values just for the customer IDs which have at least a transaction in both periods?

Thank you very much in advance.

G

[#2]

Could you share a sample qvw?

[#3]

Hi Robert,

I'm not able at the moment but I can share some data with you.

Transaction date	Customer ID	Store ID	Value	Year	Month	Week
01/02/2013	123	2	120	2013	2	5
26/02/2013	123	1	150	2013	2	9
23/03/2013	546	2	144	2013	3	12
17/04/2013	456	2	124	2013	4	16
12/05/2013	456	1	130	2013	5	20
06/06/2013	789	2	122	2013	6	23
01/07/2013	789	2	116	2013	7	27
26/07/2013	123	1	102	2013	7	30
20/08/2013	123	1	149	2013	8	34
14/09/2013	123	2	137	2013	9	37
09/10/2013	123	2	144	2013	10	41
03/11/2013	456	2	114	2013	11	45
28/11/2013	456	2	147	2013	11	48
23/12/2013	879	1	143	2013	12	52
17/01/2014	456	2	124	2014	1	3
11/02/2014	456	2	126	2014	2	7
08/03/2014	789	2	125	2014	3	10
02/04/2014	789	1	122	2014	4	14
27/04/2014	123	1	134	2014	4	18
22/05/2014	123	2	107	2014	5	21
16/06/2014	123	2	102	2014	6	25
11/07/2014	123	1	143	2014	7	28
05/08/2014	456	1	114	2014	8	32
30/08/2014	789	1	146	2014	8	35
24/09/2014	789	1	112	2014	9	39
19/10/2014	123	1	105	2014	10	43
13/11/2014	123	2	124	2014	11	46
08/12/2014	123	1	136	2014	12	50

If i choose Month = 2, I should have a result like this:

2013	2014
Store Id	How many customers?	Values	How many customers?	Values	Appearing in the same period?	Values AITSP
1	1	150	0	0	0	0
2	1	120	1	126	0	0
Totale complessivo	2	270	1	126	0	0

If I choose Month = 7

2013	2014
Store Id	How many customers?	Values	How many customers?	Values	Appearing in the same period?	Values AITSP
1	1	143	0	0	1	143
2	2	218	0	0	0	0
Totale complessivo	2	218	1	143	1	143