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You can use **proc freq **in SAS to quickly create frequency tables for one or more variables in a dataset.

The following examples show how to use this procedure with the SAS built-in dataset called BirthWgt, which contains various characteristics for 100,000 mothers that recently gave birth.

We can use **proc print** to view the first 10 observations from this dataset:

/*view first 10 observations fromBirthWgtdataset*/ proc print data=sashelp.BirthWgt (obs=10); run;

**Example 1: Frequency Table for One Variable**

We can use the following code to create a frequency table for the Race variable:

**/*create frequency table for Race variable*/
proc freq data=sashelp.BirthWgt;
tables Race;
run;**

The output table contains four columns:

**Frequency**: The total number of observations that fell in a certain category.**Percent**: The percentage of total observations that fell in a certain category.**Cumulative Frequency**: The total number of observations that have been accounted for up to and including the current row.**Cumulative Percent**: The cumulative percentage of total observations that have been accounted for up to and including the current row.

For example, from the output table we can see:

- The total number of Hispanic mothers was
**22,139**. - The percentage of total mothers who were Hispanic was
**22.14%**. - The total number of mothers who were Asian, Black, or Hispanic was
**41,496**. - The cumulative percentage of mothers who were Asian, Black, or Hispanic was
**41.50%**.

**Example 2: Frequency Table for One Variable (Sorted)**

By default, frequency tables are sorted in alphabetical order based on the category names. However, we can use the **order** function toÂ sort the categories by frequency instead:

**/*create frequency table for Race variable, sorted by frequency*/
proc freq data=sashelp.BirthWgt order=freq;
tables Race;
run;**

Notice that the categories are now sorted based on frequency from highest to lowest.

**Example 3: Frequency Table for One Variable (Include Missing Values)**

By default, missing values are not included in frequency tables.

However, we can use the **missing** command to tell SAS to include a row to count the frequency of missing values:

**/*create frequency table for Race variable, sorted by frequency*/
proc freq data=sashelp.BirthWgt order=freq;
tables Race / missing;
run;**

Since no additional row was added to the frequency table, this tells us that there were no missing values for Race in the original dataset.

**Example 4: Frequency Table for Multiple Variables**

To create a frequency table for multiple variables at once, we can simply include multiple variable names in the **tables** argument.

For example, we can use the following code to create a frequency table for both Race and AgeGroup:

**/*create frequency table for Race and AgeGroup variables, both sorted by frequency*/
proc freq data=sashelp.BirthWgt order=freq;
tables Race AgeGroup;
run;**

We can see that a frequency table was created for both variables.