Adding Functionality to Your Cube - Getting Started with SQL Server 2012 Cube Development - page 177

Scope(
{
[Measures].[Sales Amount],
[Measures].[Sales Amount - Fact
Reseller Sales]
}
);
Then the Year to Date calculation is defined. First of all, the tuple is defined that
contains the members of the calendar years and the date members together with the
Year to Date member. Then the Aggregate function is used that calculates the
Year to Date value using the PeriodsToDate function.
Note
More information about the Aggregate and PeriodsToDate functions can
be found in the online manual at http://msdn.microsoft.com/en-us/library/
ms145524.aspx and http://msdn.microsoft.com/en-us/library/ms144925.aspx .
/*Year to Date*/
(
[Order Date].[Hierarchy Order Date
Calculations].[Year to Date],
[Order Date].[Calendar Year].[Calendar
Year].Members,
[Order Date].[Date].Members
)
= Aggregate(
{ [Order Date].[Hierarchy Order
Date Calculations].[Current Order Date] }
*
PeriodsToDate(
[Order
Date].[Hierarchy].[Calendar Year],
[Order