MDX gurus - triangulation query - a solution needed for a cube

[eo]

Hi,

I will briefly explain what is required by MDX. We have two fields, and needs to be compared to each other. YearOdAccount and TransactionDate. A policy has an initial YearOfAccount, and then one or multiple TransactionDates in the same and/ or following years. The cube needs to show a triangulation of these to "dates" compared against each other.

Something like this:

2005 2006 2007 2008
Year1 1000.00 1500.00 2150.00 500.00
Year2 1200.00 1650.00 2200.00
Year3 1250.00 1800.00
Year4 1250.00

The years on the x-axis represents the YearOfAccount
The Year ref on the Y-axis represents transaction year 1 to year n

So for the YearOfAccount 2005, in transaction Year1 (2005) the sum value of policies were 1000.
In transaction Year2 (2006) another 200.00 were added to policies with a YearOfAccount of 2005 thus totalling 1200.00.
In transaction Year3 (2007) another 50.00 were added to policies with a YearOfAccount of 2005 thus totalling 1250.00.
In transaction Year4 (2008) nothing more was added to policies with a YearOfAccount of 2005 thus remaining 1250.00.

This is called a triangle as YearOfAccount 2006 will have values in transaction Year1 (2006), Year2 (2007) and Year3 (2008);
YearOfAccount 2007 will have values in transaction Year1 (2007) and Year2 (2008); and
YearOfAccount 2008 will have values in transaction Year1 (2008) only.

Any idea where to start with MDX to create this triangulation based on any cube measure viewed?

EO
Hertfordshire, England