I am in need of a variable measuring "demand for banking services" in general, on a country level. Specifically the (maximum) size of the market for banking services for a given country. This will be used as a control variable.
Does anyone know any standard proxies or measures used in the literature to measure something like "total demand for banks"? I need something general, not a specific banking service. Something that summarizes the different sources of demand for banking services, such as some kind of constructed index or so. Something that summarizes everything/most services through which banks make profits. If that is not possible, are there maybe two standard measures that each cover demand for deposits and demand for loans?
What variables are generally used? If nobody knows what is standard, does anyone have any plausible suggestions of proxies/measures for "demand for banking services"? Further, any suggestions on data sources I could use to get country level data (preferably a panel starting around the '80s or '90s) for such a variable?
The proxy/measure need not be perfect. The only important thing is that it captures "the size of the market for banking services (in general)" in some way. Especially a measure of demand that would determine the (maximum) number of banks in a given country.