By default, the MEANS procedure produces the n, mean, minimum, maximum, and standard deviation.

To specify the variables that PROC MEANS analyzes, add a VAR statement and list the variable names.

Unlike Age, Height, or Weight, the values of IDnum are unlikely to yield any useful statistics.

Unlike CLASS processing, BY-group processing requires that your data already be indexed or sorted in the order of the BY variables. You might need to run the SORT procedure before using PROC MEANS with a BY group.

A CLASS statement produces a single large table, whereas BY-group processing creates a series of small tables. The order of the variables in the CLASS statement determines their order in the output table.

You can use either PROC MEANS or PROC SUMMARY to create the table. Adding a PRINT option to the PROC SUMMARY statement produces the same report as if you used PROC MEANS.

By default, PROC FREQ creates a table for all variables in a data set.

Both continuous values and unique values can result in lengthy, meaningless tables. Frequency distributions work best with categorical values.

An asterisk is used to join the variables in a two-way TABLES statement. The first variable forms the table rows. The second variable forms the table columns.

An asterisk is used to join the variables in crosstabulation tables. The only results shown in this table are cell percentages. The NOFREQ option suppresses cell frequencies, the NOROW option suppresses row percentages, and the NOCOL option suppresses column percentages.