<p><a href=“http://www.nber.org/papers/w15954.pdf?new_window=1[/url]”>http://www.nber.org/papers/w15954.pdf?new_window=1</a> is the referenced paper; it suggests that in class time has declined as well (students missing class more?), leading to a total academic time of only 27 hours per week for full time students.</p>