Hands-On SAS for Data Analysis

LAGS

If you want to calculate a period of time between one event and another, then you should use the LAG function. This function helps to return values from a queue. The syntax has two elements:

• The first argument specifies a numeric or character constant, variable, or expression.
• The optional argument specifies the number of lagged values. The default is 1.

Let's look at lagging the variables:

Data Lag;Set Decimal (Keep = Round);Lag1 = Lag1 (Round);Lag2 = Lag2 (Round);Run;

This will result in the following output:

By specifying a single lag, we have started the LAG1 variable values from the second observation. The first observation has ...