DATASOURCE Procedure
Structure of a SAS Data Set Containing Time Series Data
SAS procedures require time series data to be in a specific form recognizable by the SAS System. This form is a two-dimensional array, called a SAS data set, whose columns correspond to series variables and whose rows correspond to measurements of these variables at certain time periods.
The time periods at which observations are recorded can be included in the data set as a time ID variable. The DATASOURCE procedure does include a time ID variable by the name of DATE.
For example, the data set in Table 1, extracted from a DRIBASIC data file, gives the foreign exchange rates for Japan, Switzerland, and the United Kingdom, respectively.
Table 1: The Form of SAS Data Sets Required by Most SAS/ETS Procedures
| Time ID | Time Series | ||
|---|---|---|---|
| Variable | Variables | ||
| DATE | EXRJAN | EXRSW | EXRUK |
| SEP1987 | 143.290 | 1.50290 | 164.460 |
| OCT1987 | 143.320 | 1.49400 | 166.200 |
| NOV1987 | 135.400 | 1.38250 | 177.540 |
| DEC1987 | 128.240 | 1.33040 | 182.880 |
| JAN1988 | 127.690 | 1.34660 | 180.090 |
| FEB1988 | 129.170 | 1.39160 | 175.820 |