SAS Certification Prep Guide, 4th Edition

Reducing Data Storage Space for Numeric Variables

Another way to reduce data storage space is to reduce the length of numeric variables. In addition to conserving data storage space, reduced-length numeric variables use less I/O, both when data is written and when it is read. For a file that is read frequently, this savings can be significant. However, in order to safely reduce the length of numeric variables, you need to understand how SAS stores numeric data.

How SAS Stores Numeric Variables

To store numbers of large magnitude and to perform computations that require many digits of precision to the right of the decimal point, SAS stores all numeric values using double-precision floating-point representation. SAS numeric variables have a maximum ...