Answer:
I would say there would be 5-10% in a city, and maybe 10-20% in the country. It mainly varies depending on how big the city is, how many people/districts there are, and the size of the country, which makes it hard to give a certain percent of shops, as there may be small businesses included as well or new shops being built.
Hope this helps! This was pretty confusing for me as well so i hope the answer is alright (×﹏×)
