Monetary policy and the yield curve

"This paper examines the empirical properties of a two-factor affine model of the term structure of interest rates, estimated with LIBOR and interest rate swap data from 1989 through 2001. Despite its relative simplicity, the model fits the interest rate data remarkably well, both across time and maturity, and identifies changes in the current and expected stance of monetary policy as primary movers of the yield curve"--Federal Reserve Board web site.