According to Zillow Mortgage Marketplace, mortgage interest rates rose sharply this week to 3.71% (up from 3.58%). This increase was due to the Federal Reserve talking about scaling back its economic stimulus plans (read: Quantitative Easing plans). Some expect mortgage rates to remain stable, but based off of the relationship between the 10 year treasury yield and 30 year mortgage rates over the past decade (as shown in this graph), interest rates should already be in the 4’s (4.14% to be exact).