Previous
Previous
 
Next
Next

Using Data from Past and Future Time Periods

Several OLAP DML functions make it easy for you to use data from past or future time periods. For example, the LAG function returns data from a specified previous time period, and the LEAD function returns data from a specified future period.

When you run a model that uses past or future data in its calculations, you must ensure that your solution variable contains the necessary past or future data. For example, a model might contain an assignment statement that bases an estimate of the revenue line item for the current month on the revenue line item for the previous month.

DIMENSION line month
...
revenue = LAG(revenue, 1, month) * 1.05

When the month dimension is limited to Apr2004 to Jun2004 when you run the model, then you must ensure that the solution variable contains revenue data for Mar96.

When your model contains a LEAD function, then your solution variable must contain the necessary future data. For example, when you want to calculate data for the months of April through June of 2004, and when the model retrieves data from one month in the future, then the solution variable must contain data for July 2004 when you run the model.