How to group the count by distinct (Set Analysis)

[dleelearn]

Attached show the distinct date of GRN  with expression: =Count({<[Trading Year]=,[Trading Month]=,[Trading Week]=,[Date]=>}distinct([Weekly GRN Date]))

Its current result shows Count of Date = 3

I would like to group it according to trading week as well so the count result =1.
 I am thinking to use aggr but show me the same result =3 .

=aggr(Count(distinct{<[Trading Year]=,[Trading Month]=,[Trading Week]=,[Date]=>}([Weekly GRN Date])),[Trading Week])

How should i do it? Pls help . 🙂

[Or]

I'm not sure I understand your request, but if you're looking for a distinct count of trading weeks, rather than dates, why not count that field rather than the date field?