_Application.ExtendList property

True if Microsoft Excel automatically extends formatting and formulas to new data that is added to a list.

Namespace:  Microsoft.Office.Interop.Excel
Assembly:  Microsoft.Office.Interop.Excel (in Microsoft.Office.Interop.Excel.dll)

bool ExtendList { get; set; }

Property value

Type: System.Boolean

To be extended, formats and formulas must appear in at least three of the five list rows or columns preceding the new row or column, and you must add the data to the bottom or to the right-hand side of the list.