Rank Function in crosstab

Hi i have a Requirement
how to find the rank in corsstab..... detail explanation below
in my report row is region,cloumn is year and measure is sales total...
I want find out the year wise rank based on measure
example below

sales-total Sales 2006 ($) Sales 2005 ($) Rank 2006 Rank 2005
Americas
Europe
Asia-Pacific
Auatralia
Africa

Use Report Studio built-in funciton RANK as illustrated below:
1. Introduce a Query Calculation/Data Item named 'Rank'
2. Copy & Paste the expression --> rank (expr/calculated column ASC/DESC)
For Example:--> rank ([tot_Sales] DESC)
3. Save and execute the report.