ShowAllItems Property [Excel 2003 VBA Language Reference]
True if all items in the PivotTable report are displayed, even if they don't contain summary data. The default value is False. Read/write Boolean.
For OLAP data sources, the value is always False.
This example displays all rows for the Month field in the first PivotTable report on worksheet one, including months for which there's no data.
Worksheets(1).PivotTables("Pivot1") _ .PivotFields("Month").ShowAllItems = True
Applies to | PivotField Object