A World Bank 2008 Report concluded that Brazil's current state of education would lead to its falling behind other developing economies, and act as a constraint on growth. Brazil's 15 year old chidren came in 49th out of 56 countries on the reading exam for the Program for International Student Assessment, with more than half scoring in the test's bottom reading level in 2006, with scores in math and science worse than that. Of the 25 million workers who could join the work force in 2010, about 22% are not considered qualified for the labor market, according to a government report. The World Bank Report says Brazil stands to miss out on the "demographic window," in which increasing numbers of younger workers make the economy more productive, unless it addresses problems in education.