The list at the bottom of the main window provides information about the variables in the current data set. Each variable's name, type (numeric or character), and label are listed, along with the variable's number of unique values or levels. The number of observations in the data set is given on the right side of the header of the variable list.
Selecting a variable from the list brings up univariate plots of that variable. For a numeric variable, a histogram, box-and-whisker plot, and line plot are produced. For a character variable, a bar chart is produced.
The variable list is updated each time you switch data sets or add or delete observations or variables from the current data set. In addition, it reflects any observation selection criteria you have specified.
If a user-defined format is associated with a variable, the number of unique values is the number of unique values as defined by application of the format to the variable.