Defining a name for multiple portfolios after monthly data download

I have been downloading a group of 25 portfolios data (with sector/security) that has corresponding monthly weight and return data. I have been naming each range every time the data downloads. The issue is that the range will not be static, meaning that next month the portfolio may add a security, extending the range to an additional row. Is there a way through a macro/VBA to name each range without doing so with a lot of manual clicks?

Can you attach a sample file with your data layout. Showing the original raw data, and a Result(after macro has been run)?