172,682 Wall Streeters will crowd rooms around the world tomorrow to take a 6-hour test - and half will fail

More people than ever before will crowd gymnasiums and auditoriums around the world to write the grueling six-hour CFA exams on Saturday.

Their odds of passing are less than 50%.

The three levels of the Chartered Financial Analyst exam are administered once a year in more than 100 countries around the world. (Level I is offered twice a year).

This Saturday, 172,682 people from 183 countries are registered to take the test. That's the highest number of registrants on record - and up from 159,889 last June - according to the CFA Institute, which administers the exam.

Kurt Schacht, a managing director at the CFA Institute, told Business Insider last year that interest in the exam has been growing pretty steadily throughout his decade of experience with the institute.

Much of that is fueled by growth in Asia, which on Saturday will account for 45% of test takers.

Schacht said that becoming a CFA charter holder is a huge leg up for anyone hoping to build a career in investment management.

As for other credentials, like MBA degrees, he said, "I honestly think there is no comparison in terms of the cost-benefit analysis." (The CFA costs $2,300 altogether, including registration fees and test fees.)

But the tests are tough. Last June, only 46% of people passed the tests - or 42% of Level I test takers, 46% of Level II test takers, and 53% of Level III test takers.

Level I tends to have the lowest pass rate, Schacht said, because that's the stage where the amateurs are weeded out from the serious players.

Successful candidates often put in up to 300 hours of study per exam.

"There's a great demand on the employer side for people that make it through this course of study, and I think that's all reflected in how difficult it is," he said.

Only about 1 in 5 people who start the CFA program make it through all three levels and successfully complete the other requirements to become charter holders, Schacht said.

Here are the historical pass rates dating back to 1963 from the CFA Institute:

Good luck!