Today, many U.S. universities not only allow admitted students to take a year off before beginning their studies, but encourage it. In 2000, Harvard's admissions officers co-authored an article titled "Time Out or Burn Out for the Next Generation," in which they suggest admitted students combat the mounting pressures of secondary and post-secondary education (and modern life in general) by taking a year off. [...] The term "gap year" caught on in the US about a decade ago, when Prince William and Prince Harry took planned time off before entering university in the UK, according to Holly Bull, president of an independent agency called Interim Programs that helps US pre-college students plan their time off. Bull's father founded the agency in 1980 to promote the concept. "I've basically watched the trend grow from its inception in the U.S.," she says. "And while I wouldn't call it mainstream now, we've seen a lot of growth." This growth has led to a burgeoning "gap year" planning services industry, populated by an increasing number of consulting agencies such as Bull's. The American Gap Association (AGA), founded in 2012, oversees this industry, acting as a kind of accreditation agency. Based on the programs it reviews, the AGA estimates that between 30,000 and 40,000 students annually take a planned "gap year" in the U.S., and that the number of students doing this has grown by between 20% and 30% each year since 2006.