Abbreviating variable names
If you have a series of variable names with the following two characteristics:
The same characters used as a prefix (Q in the above example), and
A sequential numeric suffix (1, 2, 3, 4, 5, 6, 7, 8, 9, 10),
then you can abbreviate a series of variables using the single-dash abbreviation style.
In the above example, Q1-Q5 is interpreted by the compiler exactly as though you had typed Q1 Q2 Q3 Q4 Q5.

single-dash variable abbreviation prefix#low-prefix#hi Where prefix may be a letters, numbers, or and underscore so long as the last character of the prefix is not a number. #low is a number less than #hi.

For more information see SL:R , Chapter 4 Rules of the SAS Language, Words in the SAS Language, SAS Variable Lists