An increasing number of newly-built multifamily units are found in larger buildings, as measured by the number of apartments per building. According to Census Bureau data of multifamily completions, the share of new multifamily units in buildings with 50 or more units reached a data series high of 48% during 2014.
The share of new units in large buildings (50+ units or more) has been rising steadily since 1996, after reaching a data series low of 8% during 1994 and 1995, albeit with one exception. The share declined to 28% in 2011 after recording a 43% mark for 2010. Given typical times of multifamily construction of 11 to 15 months, the large building share of multifamily development fell for construction started in late 2009 and 2010 as a result of the Great Recession.
The trend of increasing concentration of apartments in large properties holds for the broader set of residences constructed in properties of 20 units of more as well. The 2014 completion share for 20+ unit properties was 83% and has been above 50% since 2001.