Worksheet Properties dialog box should be used to change various parameters of worksheet viewer grouped on two tabs: Columns and View
Column and expression table should be used to edit column captions and expressions. Column captions describe column data and may contain arbitrary text. Columns in expressions are named by letters (a..z), not by column captions. Column expressions fields can be used to transform visible representation of data values in the same manner as for plot series. Notice that in-place editor and copy/paste commands not affected by column expressions. Besides, you can define expression for any columns, including those who have no actual data. Column expressions are displayed in the worksheet header area.
Set column as X,Y - click these buttons to mark selected column in the column table as X or Y. Columns marked as X,Y are used in various operations and may be also referenced as cx, cy in expressions.
Numeric format controls allows you to specify format type, minimal width and number of places after decimal point.