Extra pipes attracted better plumbers — the more the finance industry grew, the more it tugged at highly educated workers. Philippon is a French economist at NYU’s Stern School of Business. He and a co-author, Ariell Reshef of the University of Virginia, have shown that from the end of World War II until the early 1980s, finance was just like any other desk job: The average Wall Street worker was paid about as much as the average worker in the private sector and was only slightly more educated.

But starting at about the time that Jackson joined Goldman, when Congress began tweaking investment-tax rates, Wall Street started drawing more educated workers. This made the average finance salary go up — from less than $50,000 a year in 1981 (which is about $100,000 in today’s dollars) to more than $350,000 a year in 2012.

Salaries rose even faster in the mid-1990s. The average finance worker began to earn more than a similar non-finance worker who had the same amount of schooling. Wall Street executives began to command salaries several times the rate that non-finance executives could.

In sheer dollar terms, it became irrational for almost any qualified American graduate to pass on a Wall Street job. By the mid-2000s, finance workers earned about 50 percent more than they would have in a similar job anywhere else in the economy. There are almost twice as many financial professionals in the top 1 percent of American income earners today as there were in 1979, according to researchers from Williams College, Indiana University and the Treasury Department. Almost 1 in 5 members of the top 0.1 percent work in finance.

You might think finance workers earned all that money because they were selling new and improved financial products that delivered more value — that helped get money more efficiently from investors who had it to entrepreneurs who could put it to profitable use. Research suggests that’s not the case.

A few years ago, Philippon set out to study 130 years of financial-sector performance. He expected to find that performance improved as the industry grew in recent decades.

Philippon tracked the fees that banks and other asset managers take when they move money between investors and borrowers. In theory, the managers should charge less as their technology improves, because they become more efficient and more competitive with one another. (Or, if they charge the same amount, they should generate better returns for investors.)