According to Freddie Mac VP and Chief Economist Frank Nothaft, apartment construction is at a 25-year high, but the good news is that those units are being absorbed thanks in part to a continuing drop in home ownership rates:
Freddie attributes these absorption rates to the decline in the overall U.S. home ownership rate, which fell to 64.7 percent in the second quarter of 2014. That was the lowest mark since 1995. As home ownership falls, apartment vacancies have also dropped to their lowest level in 14 years.
Here’s a video of Northaft’s comments: