As discussed in the text, if money demand is unstable, the Fed may prefer to target interest rates rather than the money supply itself. When the Fed follows an interest-rate-targeting policy, "Fed watchers" in financial markets and the media typically look to changes in short-term interest rates rather than changes in the money supply to gauge the Fed's intentions. Graph the three-month Treasury bill interest rate and the unemployment rate, using monthly data since 1961. If changes in monetary policy are reflected primarily by changes in the short-term interest rate, what relationship would you expect to see between these two variables? Does this relationship hold up in the data?