Figure 2.9

Time spent in postdoctoral training by life-science PhDs who took postdoctoral training, 1969–1994, as reported in 1995.

Data from table E.8.

differences, for example, that almost all the increase in the life-science PhD population is in biomedical sciences, whereas there has been little or no increase in the number of nonbiomedical-science PhDs. Table E.10 shows differences by sex, race, citizenship, and top-26 universities compared to non-top-26 institutions.


  • The number of life-science PhDs awarded annually in the United States has increased by 42% since the late 1980s, and the number awarded in 1996 was more than 3 times the number awarded in 1963.
  • Foreign nationals with either permanent or temporary visas accounted for 38% of the life-science PhDs in 1996, and the number of temporary-visa holders planning to remain in the United States has risen to about 60% in recent years.
  • Almost all the increase in numbers of life-science PhDs awarded has been in biomedical fields; the number in nonbiomedical fields has remained virtually the same since 1970.
  • The median elapsed time between entry into graduate school and receipt of the life-science PhD has increased by about 2 years, from 6 to 8 years, but PhDs are obtained more quickly in some fields.
  • The federal government financially supports the education and research training of about one-third of all life-science graduate students. The almost 12,000 graduate students supported by federal research grants represent the largest support mechanism among all categories of support—federal, institutional, or self.
  • An increasing percentage of life-science PhDs do postdoctoral work, and the length of time spent in postdoctoral training is increasing.

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