The world is still paying attention to millennials and their migration habits, despite Generation Z's incoming threat. And while millennials appear to like cities, thanks to their good public transportation and myriad Apple Stores, a new study [PDF] says some of the world's biggest urban areas are in danger of losing their young people in the next 10 years

Global initiative group YouthfulCities interviewed 15,000 millennials in 34 cities all over the world, splitting them up by continent. And of those millennials, 58 percent said they planned to leave their city within the next decade, noting that they're being driven out by high costs of living, safety issues, and problems with employment.

According to the study, millennials were more likely to want to stay in their current city if it was a "youthful" city, meaning it has a government that listens to and addresses issues relevant to young people; that there is access to fulfilling jobs; that the city is safe; that its inhabitants are healthy and have access to health services; that the city has post-secondary education programs for jobs that are available; and that the city boasts clean, open, and welcoming green space. In North America, affordability was the biggest issue, followed by employment, safety, and effective public transportation.

The good news is, things seem to be going okay for millennials in North America, even though only 29.4 percent of respondents said their governments listen to them (and it can get worse!) 79 percent of the North American millennials surveyed said they were happy, topping the list of continents. 71.7 percent were healthy, which was also the highest out of all the continents, and 35 percent were employed. Interestingly, though, 17 percent were unemployed and a staggering 26 percent were employed part-time, the highest percentage out of all the continents by at least 10 percent. Only 26 percent thought they'd be better off financially than their parents in the long run—globally, 31 percent of respondents thought they'd be better off.

Not a single city in the United States won one of the study's "awards"—Montreal came in #1 in terms of having a sympathetic government; Berlin had the best city for cyclists; London has the most youthful Mayor (really?); Warsaw has the best public transit; Moscow has the best financial prospects; Mumbai has the best entrepreneurial spirit, and Addis Ababa is the best for skateboarding, which, yes, warranted its own award.

Still, the good ol' US of A got some due. New York won notice for its contribution to film, music, and fashion among youths; while San Francisco got nods for its commitment to the environment, job opportunities, and entrepreneurial spirit. No one mentioned Buffalo, although I hear that that's where all the kids are going these days.