A big year for development has pushed up vacancy in 2017 in the 123,900-unit St. Louis apartment market. The October vacancy rate was 5.2%, not high but up 60 basis points year-to-date on 1,699 units of new supply and 881 units of net absorption. The rate had been 9.2% at the end of 2009. Overall rents were up by 3.9% asking and 2.9% effective year-to-date through October 2017 to $890 and $846 per month. The lower effective rent gain shows an increase in concessions.