Mortgage security hedging and the yield curve

The authors find that the use of Treasury securities to hedge mortgage-backed security extension risk may have magnified increases in long-term interest rates after the tightening of monetary policy in early 1994. Substantial increases in the duration of mortgage securities appear to have caused realignments of hedges and portfolios that, in turn, had a significant impact on the short-run movements of the Treasury market, particularly for ten-year securities. This phenomenon may have altered the short-run dynamics of the yield curve and thus changed the transmission of monetary policy.