The study talks about how more young people are residing with their parents because of economic difficulty, but I'm not sure that's necessarily a major factor in the decline. Many people become sexually active before they move out of their parents' houses, and although it might be more challenging to find a private space, where there's a will, there's a way. Teenagers have been sneaking around to fool around for generations, and I don't think teenagers and young people of today are any less adept at finding a way to shack up if they're sufficiently determined.

So I think the focus is about what forces were not present in previous generations, and the Internet is certainly the most conspicuous factor. I'm not saying it's the decisive factor, but I'm not surprised it's a prime culprit.