I recently assisted a XamPivotGrid customer who was trying to load Excel data containing separate Month and Year columns (e.g., '01', '2011').  I discovered that this functionality is not possible with the current version (10.3) but will be available with the next release (11.1).

The current XamPivotGrid help documentation for loading Excel Data is located here: http://help.infragistics.com/NetAdvantage/DV/2010.3/CLR4.0/?page=xamPivotGrid_US_Excel_Spreadsheet_As_A_DataSource.html

The following code (taken from the help doc above) does NOT work for the Month/Year column use case:

flatDataSource.Columns = DataSourceBase.GenerateInitialItems("[Date]");

.

.

.

HierarchyDescriptor dateTimeDescriptor =

            new HierarchyDescriptor

            {

                AppliesToPropertiesOfType = typeof(DateTime)

            };

            dateTimeDescriptor.AddLevel(date => "All Dates", "All Values");

            dateTimeDescriptor.AddLevel(date => date.Year, "Years");

            dateTimeDescriptor.AddLevel(date => date.Date, "Members");

                                      

Below is a code snippet provided by our engineers to work with the 11.1 version of the XamPivot Grid.  I expect our 11.1 version of the documentation to have this code, or something similar.  However, for those awaiting this functionality in 11.1, this is for your reference.