Stats

Placing consecutive dates in a column of an SPSS file (January 26, 2005).

Someone gave me a data set with 549 rows of data. The first row corresponded to observations on 06/01/2003, the second to 06/02/2003, and so forth through 11/30/2004. She wanted to know how to get those particular dates in a column without having to type something into each individual cell.

Here's how I did it.

First, I defined a new column, date1, that has a date format. Then I used TRANSFORM | COMPUTE to calculate the following formula:

DATE.DMY(31,05,2003)+$casenum*24*60*60

This gives you dates starting on June 1, 2003 and moving up day by day in each row.

She also wanted a column designating the particular month. You can do this with the same TRANSFORM | COMPUTE command to compute a new variable, MONTH, using the formula

XDATE.MONTH(date1).

Since you have June in both 2003 and 2004, you probably also need to compute a YEAR variable using the formula

XDATE.YEAR(date1).

This is a very simple example of date calculations in SPSS. I have another page that talks about this:

Stats: Date calculations in SPSS

and version 13 of SPSS has a very useful date and time wizard:

Stats: New in SPSS version 13.0 (December 7, 2004)

but the best resource for these types of things is on Raynald Levesque's web site:

Dates Tutorial. Levesque R. Accessed on 2001-09-07. pages.infinit.net/rlevesqu/LearningSyntax.htm#DateTutorial

07/08/2008. Category: SPSS software