Date:         Fri, 22 Jan 2010 12:49:02 +0100
Reply-To:     Daniel Fernández <fdezdan@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Daniel Fernández <fdezdan@GMAIL.COM>
Subject:      Re: Lag function-quarterly data
Comments: To: SAS user <sasuser4@googlemail.com>
In-Reply-To:  <20e5d12f1001220329p508e73bfoaa40b51d6f44dc92@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

If you want to compare one quarter with last quarter, this is a
possile solution:

proc sort data =have out=need; by id  yearqtr;run;

data need2;
do until (last.id);
set need end=fin;
by id yearqtr ;
output;
var1_last_qtr= variable1;
var2_last_qtr= variable2;
end;
if first.id then do;
var1_last_qtr= .;
var2_last_qtr= .;
end;
run;


Daniel Fernandez.
Barcelona

El día 22 de enero de 2010 12:29, Daniel Fernández <fdezdan@gmail.com> escribió:
> hi,
>
> how mnay lags you want? Do you compare 1974Q3 to 1974Q2 ? Or 4 quarters a year?
>
> Daniel
>
> 2010/1/22 SAS user <sasuser4@googlemail.com>:
>> Here is a sample of my data; I have around 600,000 observations
>> ID      yearqtr variable1       variable2
>> 006 1974Q4 200             300
>> 006     1974Q3  100             153
>> 006     1974Q2  360             256
>> 006     1974Q1  256             369
>> 006     1975Q4  369             257
>> 006     1975Q3  596             589
>> 006     1975Q2  965             125
>> 006     1975Q1  259             789
>> 005
>>
>>
>> etc
>>
>>
>>
>> 004
>>
>> etc
>> Any suggestions will be greatly appreciated.
>>
>