Data on listed companies, and therefore the number of law departments: for every 1 million in population, 10-35 companies (and thus law departments)
Ten years or so ago, 18 countries deemed to operate under a common law system boasted 35 companies listed on a stock exchange for every million people in the country. Thus, if the United States had about 250 million residents when the article was published in the Economist, April 19, 1997 at 78, and since its ratio was 30, it would have had about 7,500 quoted companies.
For 21 French civil-law countries, however, including among them Indonesia, Mexico and Spain, they average only 10 listed companies per million residents. In six countries that legal scholars classify as German-type legal systems, which include also Japan, South Korea and Taiwan, the average was 16; for four Scandinavian countries, which form a third group of civil law countries, it was 27. If something similar to those ratios holds today, we have another tool to estimate the number of legal departments that flourish in the largest countries. For example, if we lop off half the population of the world as being less developed, the remaining 3 billion in population would suggest about 61,000 public companies and therefore law departments (using the overall average of 22 per million capita).
The article also shows stockmarket capitalization as a percentage of gross national product among the four groups. The common law countries in 1994 stood at about 60 percent of GNP. The German group showed 45 percent, the Scandinavians 30 percent, and the French lagged at 20 percent. We might well extrapolate legal intensity and corresponding workloads on law departments in line with those figures.
These fascinating insights came from the original research published in the Journal of Finance, Vol. 52, no. 3 (1997): 1131-1150 by Rafael La Porta and three other authors.