The average full-time working American makes $51,350 a year, according to data collected by Glassdoor in April . That's $4279 per month, before taxes.

Facebook interns, the top-earning summer interns in the country, make an average of $8,000 per month, according to Glassdoor. If a Facebook intern worked for 12 months, that would come out to a salary of $96,000.

Getting a job at a major tech or finance firm, even as a summer intern, often means surpassing much of the rest of the country financially.

In general, tech and finance jobs pay more than other industries, the Glassdoor data shows. And jobs in big cities like New York and San Francisco generally pay more than similar jobs in other parts of the country because the cost of living is higher.

Still, of the 25 highest-paying internships, the last on the list, Bank of America, pays summer interns $4,570 per month. Annualized, that's $54,840, which is about $3,000 more than the median U.S. salary.

If the intern pay at these companies is impressive, the wealth of the executives is truly staggering. Facebook CEO Mark Zuckerberg is worth almost $64 billion. Amazon CEO Jeff Bezos is worth $81 billion. Sergey Brin, the President of Google's parent company Alphabet, is worth $43 billion.

Outside the flush tech and finance industries, though, the outlook for the vast majority of American is less cheery.

A working paper published in December by the National Bureau of Economic Research written by three university professors showed that wage inequality in the United States is getting more and more severe. The rich are getting richer and the poor are staying poor.

The average pre-tax income of the bottom half of American adults has held at about $16,000 since 1980, the report finds, according to the NBER paper. Meanwhile, the average pre-tax income of the top one percent of American adults has risen from $420,000 to $1.3 million from 1980 to 2014.

See also:

Facebook, Apple, Google and the 22 other companies offering America's highest-paid internships

The 17 best jobs in America that pay over $100,000

The 50 best jobs in America in 2017