This is a condensed version of the original article.
Fannie Mae and Freddie Mac are government-sponsored enterprises (GSEs) with the stated objective of promoting home ownership by improving the availability of mortgage financing for private households. These enterprises engage in two separate and distinct lines of business: (i) assembling and marketing pools of mortgages on which they guarantee the timely payments of principal and interest and (ii) purchasing mortgage assets for their own portfolio, mostly funded with debt securities. This article examines the sensitivity of the returns on GSEs equity shares to realizations of interest rate risk. The study shows that the market value of Fannie Maes and Freddie Macs equity is vulnerable to increases in short-term interest rates and changes in the term spread (the difference between the long-term and short-term interest rates).