SAS Certification Prep Guide: Base Programming for SAS 9, Third Edition

Using Permanently Assigned Labels and Formats

You have seen how to temporarily assign labels and formats to variables. When you use a LABEL or FORMAT statement within a PROC step, the label or format applies only to the output from that step.

However, in your PROC steps, you can also take advantage of permanently assigned labels or formats. Permanent labels and formats can be assigned in the DATA step. These labels and formats are saved with the data set, and they can later be used by procedures that reference the data set.

For example, the DATA step below creates Flights.March and defines a format and label for the variable Date. Because the LABEL and FORMAT statements are inside the DATA step, they are written to the Flights.March data ...