Past 3 month graph

[#1]

I am attempting to have a graph filter for the last 3 months when a month is selected. For example, if April is selected as a filter, then in the graph it will show February, March, and April. I understand the AddMonths function can select previous months if using a negative value, however, it always just selects one. I can't seem to find a way to make it select all 3. I know it is a logic problem, I just can't seem to get the right answer. Any suggestions would be appreciated. Thank you.

[#2]

Can you attach a sample file please. Its easier to debug.

[MK_QSL · Accepted solution]

Consider that you have below data...

From Date field we have created MonthYear which can be used in your chart...

=========================================

Load

  *,

  Month(Date) as Month,

  Date(MonthStart(Date#(Date,'DD/MM/YYYY')),'MMM YYYY') as MonthYear

Inline

[

  Date, Sales

  15/08/2013, 120

  22/09/2013, 100

  05/10/2013, 1000

  15/11/2013, 280

  28/12/2013, 75

  01/01/2014, 100

  10/02/2014, 150

  25/03/2014, 250

  11/04/2014, 110

  15/05/2014, 300

  15/06/2014, 600

  10/07/2014, 240

  05/08/2014, 100

];

==============================================

Create a Bar Chart or Straight Table

Dimension

MonthYear

Expression

SUM({<MonthYear = , Date = {'>=$(=AddMonths(Max(MonthYear),-2))<=$(=AddMonths(Max(MonthYear),1))'}>}Sales)

==============================================

Create a list box for MonthYear and try to select any MonthYear...

Hope this is what you want...

[#4]

It was able to do what I did originally, it shows the first 3 months like I want it to, however, if you click on a month, it just filters down to that month, instead of also showing the 2 previous months according to that month

EDIT: I was doing some more testing and when you click on a month, it will show the previous 3 months for the month, but it will still keep whatever was last seen, is there a way to get rid of the months after the one clicked one?

EDITEDIT: So I figured out the problem, had misspelled the second statement, which is why it did not have a max, thanks so much for your help.