The Journal of Real Estate Finance and Economics

, Volume 6, Issue 3, pp 251-275

First online:

The pricing of FIREARMs (“Falling Interest Rate Adjustable-Rate Mortgages”)

  • Bjorn FlesakerAffiliated withDebt Markets Group, Merrill Lynch & Co., World financial Center
  • , Ehud I. RonnAffiliated withDebt Markets Group, Merrill Lynch & Co., World Financial CenterCollege and Graduate School of Business, University of Texas

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The purpose of this article is to propose and price a new type of adjustable-rate mortgage: the FIREARM (“Falling Interest Rate Adjustable-Rate Mortgage”). The interest payments on this mortgage adjust downward whenever interest rates decline, while remaining stable when interest rates increase. The FIREARM is alternatively priced as a prepayable and non-prepayable mortgage with a spread over the short-term interest rate. We price these two instruments and contrast their prices with those of fixed-rate mortgages using the parsimonious assumptions of a non-stationary arbitrage-free binomial term structure model.

Key words

Adjustable-rate mortgages Non-stationary arbitrage-free binomial term structure model