SSRS - Ignore single aggregate value when drilling down

I am new to SSRS and I am creating a Drill Down report. This report is comparable to a sales report by loc开发者_如何学编程ation. Let's say Country - Region - City with subtotals for each group.

The data provided for this report is not always complete. So let's say for the country "United States" all the sales are in "No Region", and all sales in "No Region" are in "No City". When drilling down, if the only region is "No Region" I want to drill down to the next level right away instead of having the "No Region" value there, that I have to drill down through again.

For illustration:

How can I achieve this? I have extensive programming knowledge (.NET) if this is necessary.

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For the detail row group, set the initial visibility to

=CountDistinct(Fields!city.Value,"table1_Region") > 1

For the City group, set the initial visibility to

=CountDistinct(Fields!region.Value,"table1_Country") > 1

Replace field and group names to match your own.