How to display nil values using set analysis

[#1]

Dear Friends,

I have a expression like highest number of invoices based on Reason, this expression works fine but what I need is when there is no data it should display No value or Nil, is it possible using straight table.

=if(aggr({1}rank(Count([Invoice])),[Reason]) = 1,Count([Reason]))

Regards

Chriss

[SunilChauhan]

may be one of this one

if(aggr({1}rank(Count([Invoice])),[Reason]) = 1,Count([Reason]),'NO Value')

or

if(aggr({1}rank(Count([Invoice])),[Reason]) = 1,Count([Reason]),'Null')