topic Percent difference from "fixed" previous period in SAS Visual Analytics

Percent difference from "fixed" previous period

Kroken — Wed, 03 May 2017 08:26:55 GMT

HI -

I'm new to SAS VA and this community and would like to see if anyone here can help me to solve a problem I have when designing a report. I want to create a graph showing percent difference from a fixed previous period (the first date in my data). I do not really understand how I can achieve this from the optional settings in the aggregated measure editor. Does anyone have any kind of solution for this?

Kind regards,

Mats

P.S It doesnt have to be solved within the editor - any solution woud be greatly appreciated.

Re: Percent difference from "fixed" previous period

RW9 — Wed, 03 May 2017 09:09:49 GMT

Well, I don't use VA so my answer here is going to be general SAS code. What I would do, and its per the models in my field, is to extract the baseline value, then merge that back to the original data. So (and you have not posted and test data in the form of a datastep so this is just example):

Some examplpe data:

Id Period Result

1 1 123

1 2 345

1 3 456

data base (rename=(result=base));
  set have;
  where period=1;
run;

data want;
  merge have base;
  by id;
run;

Now in this case, all records in the original dataset have a column base from the fixed period, and you can calculate across.

Re: Percent difference from "fixed" previous period

Sam_SAS — Wed, 03 May 2017 12:42:35 GMT

If the reference date can be hardcoded, then you could use the PeriodWithDate operator.

For example, you might use an expression like this to compare the values of Sales for each month to the value from JAN2015:

Period(_Sum_, 'Sales'n, 'Date'n, _ByMonth_) - PeriodWithDate(_Sum_, 'Sales'n, 'Date'n, _ByMonth_, '01JAN2015'd)

Documentation for Period() and PeriodWithDate() can be found here:

http://support.sas.com/documentation/cdl/en/vaug/68648/HTML/default/viewer.htm#n1lxnqfip132can1hdzuerib7i76.htm

Hope that helps.

If the first date in the data set needs to be determined dynamically, I don't think that can be done easily in the expression editor. You will need to use SAS code in your data query to evaluate it.

Sam

Re: Percent difference from "fixed" previous period

Kroken — Wed, 03 May 2017 14:57:35 GMT

Thanks - both of you!