GOOD MONEY AFTER BAD:

In fact, the push for better education is an experiment that has already been carried out globally. And, as my Harvard colleague Lant Pritchett has pointed out, the long-term payoff has been surprisingly disappointing.

In the 50 years from 1960 to 2010, the global labor force's average time in school essentially tripled, from 2.8 years to 8.3 years. This means that the average worker in a median country went from less than half a primary education to more than half a high school education.

How much richer should these countries have expected to become? In 1965, France had a labor force that averaged less than five years of schooling and a per capita income of $14,000 (at 2005 prices). In 2010, countries with a similar level of education had a per capita income of less than $1,000.

In 1960, countries with an education level of 8.3 years of schooling were 5.5 times richer than those with 2.8 year of schooling. By contrast, countries that had increased their education from 2.8 years of schooling in 1960 to 8.3 years of schooling in 2010 were only 167% richer. Moreover, much of this increase cannot possibly be attributed to education, as workers in 2010 had the advantage of technologies that were 50 years more advanced than those in 1960. Clearly, something other than education is needed to generate prosperity.

As is often the case, the experience of individual countries is more revealing than the averages. China started with less education than Tunisia, Mexico, Kenya, or Iran in 1960, and had made less progress than them by 2010. And yet, in terms of economic growth, China blew all of them out of the water. The same can be said of Thailand and Indonesia vis-à-vis the Philippines, Cameroon, Ghana, or Panama. 

Again, the fast growers must be doing something in addition to providing education.

The experience within countries is also revealing. In Mexico, the average income of men aged 25-30 with a full primary education differs by more than a factor of three between poorer municipalities and richer ones. The difference cannot possibly be related to educational quality, because those who moved from poor municipalities to richer ones also earned more.

And there is more bad news for the "education, education, education" crowd: Most of the skills that a labor force possesses were acquired on the job. What a society knows how to do is known mainly in its firms, not in its schools. At most modern firms, fewer than 15% of the positions are open for entry-level workers, meaning that employers demand something that the education system cannot - and is not expected - to provide.

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