I know exactly what this means, but this is intrinsically a fuzzy category. There is a local shopping street near us that I am sure doesn't make the grade because it is orders of magnitude smaller than the huge shopping areas off in 2 directions, even though it contains in 3 or 4 blocks:

* a drycleaner, * a dentist, * a pharmacy, * a couple of hairdressers, nail bars and similar grooming/beauty businesses, * several takeaway restaurants and coffee shops/cafes, some more upmarket than others, * a deli, * a clothing shop * a couple of "corner shop" supermarkets and hardware / general household goods shops (but no major chains), * a post office and a bank machine (but no bank branch).

I'm sure that if it was scaled up and/or joined up with similar up the road that does contain a small Sainsburys, it would be "a high street". But where do you draw the line? Is there a clear rule that divides it? If a bank or major chain supermarket moves in, does it become one? If a bank branch closes down, as they do these days, is a street no longer a high street? If we all shift to online banking, does the definition change?

This is basically the "bald man paradox" of fuzzy categories. So there never can be a fixed, definitive count.*