attrition = ？

Context:

At present, only 6% of all 24-year-old Americans hold an undergraduate degree in STEM disciplines; for African Americans, Hispanics, and Native Americans, the percentage hovers at 2 to 3%. To reach a national target of 10% (a target already achieved by several countries), the United States will need to quadruple the number of underrepresented minorities with undergraduate degrees in these disciplines. A good place to start is retaining those minority under-graduate students who begin their studies in pursuit of degrees in STEM fi elds. At present, only about 20% of minority STEM aspi-
rants complete STEM degrees, compared to 33% of white STEM aspirants. Preventing attrition will raise the number of minority doctoral students and will likely boost interest among younger minority students. Increased retention will require increased fi nancial support; the Academies 2010 report estimates that such support would require $150 million per year to start. An urgent task for colleges and universities is to redesign fi rst-year STEM classes to encourage active learning and collaboration. Engaging students through these types of classes should improve the performance of all students, and it could be particularly helpful in reducing the high rate of attrition for many minorities in STEM subjects.