Congressional Research Report updated July 23, 2008
In 2005, the foreign student population earned approximately 34.7% of the doctorate degrees in the sciences and approximately 63.1% of the doctorate degrees in engineering. Students on temporary resident visas earned 30.8% of the doctorates in the sciences, and 58.6% of the doctorates in engineering.
Full Report: http://www.fas.org/sgp/crs/misc/97-746.pdf (pdf)
