The University of Chicago’s Booth School of Business tops the latest ranking of MBA programmes by The Economist.

The clear winners in this year’s ranking have been North American schools.

“It is not just that they occupy seven of the top 10 places, including the top four slots: Chicago (Booth), Dartmouth (Tuck), California at Berkeley (Haas) and Harvard. It can be found further down our table, where middle-ranking American schools have leapfrogged their European counterparts, said The Economist.

This year’s ranking, the ninth published by The Economist, is probably the most turbulent in its short history. Usually, schools move up or down just a few places year on year. This time around, however, swings have been wilder, the report said.

The main reason for this is the difficult job market. A school’s ability to open new career opportunities for its graduates and the salaries those graduates can expect to be paid have a combined weight of 55 per cent in the ranking. The careers data in this year’s ranking are from 2009, when the situation was bleak for almost everyone.

European MBAs are still likely to out-earn the rest when they graduate—they tend to be older with more work experience—but the gap has narrowed. London Business School, which has traditionally placed its graduates in high-paying finance roles, is a good example.

As banking jobs disappeared, the average basic salary of new MBAs from LBS has dropped from $117,000 to $100,600 since the 2009 ranking. Likewise the number of students in employment within three months of graduation fell from 91 per cent to 81 per cent. At IMD in Switzerland, meanwhile, salaries fell from $127,200 to $114,415.

This compares badly with many of the American schools where the drop has not been as dramatic. At some, indeed, salaries were almost unchanged—for example the University of California at Berkeley, whose graduates made $108,400 on average.

Another area where many schools have struggled is in maintaining the quality of the student body. As the downturn became prolonged, so students began to question the wisdom of handing over huge tuition fees for uncertain returns.

The top American programmes have not lost their allure, though. The Economist uses the average score in the GMAT entrance exam as a proxy for students’ intellectual prowess. Chicago reports that its students scored an average of 717 (out of a possible 800), which is up on last year. And even this is still behind the 730 claimed by students at Stanford. In contrast, the two highest-ranked European schools, Spain’s IESE and Switzerland’s IMD, both reported lower GMAT  scores this time—683 and 671.

The highest-ranked Asian and Australasian schools have also had a testing year. Again, this has much to do with facing a difficult jobs market. At Melbourne Business School—the region’s top-ranked—graduates’ salaries have also fallen. At Hong Kong University, meanwhile, students found jobs in only five different industry sectors; last year’s score was 11.