The Federal Reserve voted to leave interest rates alone at its September meeting. Nevertheless, investors should not get too comfortable because December is very much on the table, said Collin Martin, director of fixed income at Charles Schwab (SCHW) - Get Report . Martin believes a hike in December is still likely because economic data, while having slowed a bit recently from earlier this year, appears to be good enough. Inflation appears to be trending in the right direction, with CPI rising by 1.1% in August, with core CPI rising by 2.3%, matching the high of the post-crisis recovery. He also points out that the yield curve has been steepening lately, after being in a declining trend for over two years. In the short-run, he thinks it can continue to steepen more. Martin recommends investors shorten their average duration since he does see short-term yields rising more. He also advocates floating-rate investments because the coupons on investment grade floaters can reset higher once the Fed hikes rates again, and their prices are relatively stable due to their high credit quality and low duration.