The Assignment statement
The syntax of the assignment statement is as follows.

Assignment statement (data step only) variable-name = expression; When the assignment statement is executed, the value of expression is determined and the value is assigned to variable-name.

Note that this statement is an exception to the rule: "All SAS statements begin with a keyword and end with a semicolon." How do you suppose the compiler identifies that a statement is an assignment statement?

Recall that _N_ is an automatic variable available in the Data step. It increases by 1 at each execution of the Data step and in this case will have the values of 1 thru 9.