Studies by Property and Portfolio Research indicate there's a fairly large subsection of the rental market that developers may be forgetting about. Although married couples (with and without children) still account for the largest overall share of renters with 26%, single moms and single women together comprise close to 40% of renters. The report says "Developers may want to think about how to design new apartments, or renovate existing communities, so single moms feel at home. Kids’ rooms and outdoor play areas might take precedence over rooftop lounges." Read more in the Wall Street Journal.