I am trying to create an index that is dynamic and will respond to filters.  For example, I want to rank order all products by sales, worldwide, from 1 to n.  Then, I need to see them in rank order by country.  I want to see the rank from 1 to n, without a gap in numbering.  And then, see them in rank order by department, again without a gap in the numbering.  I have been unable to find anything to create the rank ordering.  Can you help?