Developers may be catering to Millennials with their multifamily developments in the pipeline, but an older generation is also spurring demand for rental units. Baby Boomers have accounted for more than half of the country's rental growth in the past 10 years. As more Boomers reach retirement age and become empty nesters, they're selling their single-family homes and testing the rental waters.

Baby Boomers like what they see. Today's apartments, with condo-quality finishes and amenities packages that were unheard of when they were the age of Millennials today, are attractive lures for Boomers, according to the Chicago Tribune. Even though Boomers came of age wanting to buy homes as an investment (AARP says 74% of homeowners still want to hold onto their homes), overall homeownership among Boomers fell 5% from 2005 through 2013, and a growing number of Boomers don't want their money tied to a mortgage or to deal with the headaches of homeownership.

This will bode well for developers in the future. As more Boomers reach retirement, they're going to have plenty of options from the nearly 9,000 apartments in Chicago's downtown pipeline. [Trib]