After reaching an unprecedented peak of 7.6% at the end of 2015, the vacancy rate in the 38,200-unit Fairfield County apartment market fell to just 5.6% at the end of 2017. The decrease was 190 basis points in 2017 alone. The reason is the end of a development boom that peaked at 2,099 units added in 2015, followed by 1,159 in 2016 and just half that in 2017. The average asking rent increased 1.7% over the year to $2,109 per month, but the average effective rent increased just 0.2% to $2,012 per month. The fourth quarter gains were 0.7% and 0.6%, respectively. Occupancy was flat in January 2018, with the average asking rent up 0.4% but the average effective rent down 0.3%.