Physics PhDs conferred by US institutions rose 38% between 2004 and 2008, the sharpest upswing in more than a decade, according to the latest survey data released by the American Institute of Physics in College Park, Maryland. Patrick Mulvey, lead research associate for the institute's statistical research centre, says the increase corresponds to a rise in enrolments in the early 2000s that was driven by an uncertain international economy and by improvements in the undergraduate culture of physics departments. Preliminary PhD totals for 2009 and 2010 show a similar trend, Mulvey says.