A new study finds that many homeowners neglected a chance to save money by refinancing their mortgages. After the recession, the Fed took action to boost the economy by pushing interest rates to record lows. In December 2010, 20 percent of American households with fixed-rate mortgages should have taken advantage of the low rates by refinancing—but didn’t. The median homeowner could have saved over $45,000 over the life of the loan. When lending non-profit Neighborhood Housing Services of Chicago organized a mailing campaign offering refinancing help, just 17 percent of recipients refinanced. 25 percent later said they never opened the letter. An additional 25 percent said they meant to follow up but never got around to it.