Sum from current date to the last date of sales

Question

Hi 
It's been a while since I used MDX last time. 
I have a simple question (probably). I need a measure which sums up from the current date to the last sale date. 
It's like a reversal of Year To date.  And I need to do it date level. 
Let's say is the sales goes like
1/May/2000     $1000
2/May/2000     $1000
3/May/2000     $1000
4/May/2000     $1000
5/May/2000     $1000
I need to create a measure which displays sum of current sales and last sales
1/May/2000     $5000  
2/May/2000     $4000
3/May/2000     $3000
4/May/2000     $2000
5/May/2000     $1000
I have a date hierarchy and hope it can be rolled up. 
And I tried like something like ( suggested in another posting)
[Date].[Calendar].CurrentMember:NULL}
But this does not work for me.
The actual MDx I wrote is 
With member MEASURES.ActiveLicences as 
sum ( 
{[License Expiry Date].[FinancialYear].[YY-MMM].CurrentMember: null},
[Measures].[No of Students]
select {
MEASURES.ActiveLicences,
[Measures].[No of Students] } on columns, 
[License Expiry Date].[FinancialYear].[YY-MMM].members on rows 
from [Sales];
Can anyone help me with this please? 
Kind regards
Mark Kim

Answer 1

Hi SQLMa ,
I was trying a similar code, using a hierarchy expression instead of a member expression for the CurrentMember functionality . Here is an Adventure Works example :
With member MEASURES.ActiveLicences as 
sum ( {[Delivery Date].[Fiscal].CurrentMember: null}
, [Measures].[Internet Sales Amount]) 
select {MEASURES.ActiveLicences,[Measures].[Internet Sales Amount]} on columns
, [Delivery Date].[Fiscal].[Month].members on rows 
from [Adventure Works]
Hope it helps :)
Regards, David .