More than one-third of new physics PhD graduates in the United States accepted 'potentially permanent' positions across all sectors in 2013 or 2014 — the highest proportion in a decade, according to a survey by the American Institute of Physics in College Park, Maryland, which tracks education and employment trends in physics. In 2010, about 29% of physics PhDs took potentially permanent jobs, and in 2004, only about 25% had accepted such work. Of the PhD graduates in 2014 who specialized in applied physics or optics and photonics, more than half had accepted potentially permanent jobs. Overall, 10% of physics PhDs in 2014 took other temporary jobs, including roles such as visiting professor, lecturer and research scientist. The survey also found that 47% of the graduate cohort had accepted a postdoctoral fellowship, with students of nuclear physics being the most likely to accept such a position. About half of those who had taken a postdoc but were not from the United States said that visa restrictions influenced their decision. The number of physics PhDs who move on to postdoctoral research has been falling since 2010, when nearly two-thirds accepted such a post.