A non-standard interest rate floor in which the rate used is a swap rate with a constant maturity. For example, a CMS floor could put a downward limit on a 5-year swap rate. CMS floors are useful instruments for investors willing to hedge positions in long-term interest rates on expectation the rates will go down faster than the yield curve predicts. Like a normal interest rate floor, which consists of a series of floorlets, a CMS floor can also be viewed as a set of CMS floorlets.