Multifamily buildings constructed before 2010–approximately 13 years old or older—have posted strong rent growth of 4.6% on average over the last decade versus 3.4% for buildings after that benchmark, according to CBRE. 

The trend is mostly due to the fact that the older buildings have had lower average rents, leaving more room for growth since demand has intensified in the housing sector. The older properties have also experienced less volatility in their rent swings up and down or as the report said, "have been less affected by external shocks like recession." This is known from CBRE's analysis of the overall annual performance of multifamily properties since 1998, a time period that has experienced three recessions.

CBRE also has gleaned helpful information that helps investors make smart decisions about the trajectory of future rent growth based on the age of the property and how long it is held. It has found that it takes two decades for annual rent growth to outpace the long-run market average of 2.7%. The first year after construction average annual rent growth is 3.8%. In the third decade, rent growth speeds up more and peaks between 3.5% and 4%.