Graph the current yield curve (see the section, "Time to Maturity," p. 277 and the graph of the yield curve on p. 148), plotting the interest rate on bonds with different maturities against their time to maturity, using data from the Federal Reserve's H. 15 release (www.federalreserve.gov/releases/h15). Use the Fed's "constant maturity" series of rates, which are designed for this purpose. Then look at the H. 15 release from one year earlier and plot the yield curve for that date as well. What has happened to the term structure of interest rates over the past year? What economic events do you think have led to this change?