Wednesday, April 10, 2013

Interest rate graphs

Where are interest rates going? Here are two fun graphs I made, for a talk I gave Tuesday at Grant's spring conference, on this question. (Full slide deck here or from link on my webpage here)



Here is a graph of the recent history of interest rates. (These are constant maturity Treasury yields from the Fed)  You can see the pattern:


Early in a recession, interest rates fall, but long rates stay above short rates. These are great times for holders of long-term bonds. They get higher yields, but prices also rise as rates fall, so they make money both ways. But you also see the see-saws. Interpretation: long-term bond holders are getting a premium for holding interest rate risk at a time that nobody wants to hold risks.

Then there is the flat part at the bottom of the recession. Now long-term bond holders get the yield, but interest rates don't change. Still, they're making money.

Then comes the interest rate rise, when long-term bond holders lose money. Obviously, you want to get out before interest rates start rising. But it's not easy. Nobody knows for sure how long recessions will last. (That seems to be the lesson of  more serious work too.) Look at all the fits and starts, all the zig zags in long interest rates. You don't want to be caught napping like in 1994. But if you, like me, thought last year or the year before looked like 1994, you got out too early. Welcome to risk and return. Notice in 2003 that long rates started rising long before the Fed did anything.


As I look at the fundamentals, current rates look pretty low. Will inflation really average less than 3% for the next 30 years, so you just break even on 30 year bonds?  But the criticism, "if we're in such trouble, why don't markets see it coming?" is still troublesome. So let's look at the actual market forecast


The solid blue line and red line are today's yield curve and forward curve. (This is the G├╝rkaynak, Sack, and Wright data). The blue forward curve is the market expectation of where interest rates will go in the future. You can lock in these rates today, so if you really know something different is going to happen, you can make a fortune. (This is why I'm not persuaded by arguments that the Fed is driving down rates below market expectations.) We can interpret this blue forward curve by the "consensus forecast." The economy slowly recovers, interest rates slowly rise back to normal levels (4%) consistent with 2% inflation and 2% real rates. The fall back to 3% rates at the long end of the curve seems a bit low, but that's the market forecast and always a good place to start prognosticating.

If the path of future interest rates follows the blue forward curve, there is no bloodbath in long term bonds: you earn this rate of return on bonds of all maturity at every date going forward. (Proving this is a good finance class problem.)

How good are market forecasts though? This may be the market's best guess, but a lot of the future is simply unknowable.  The thin blue and red lines show the forward curve and yield curve in April 2010. You can see that at the time, the consensus market forecast was for interest rates to rise starting sooner, and to rise more quickly. We all expected the recession to end quickly, as recessions usually do.

In 2010, the market forecast that today's interest rate would be 3.5%, not zero. I graphed that forecast and realization by the leftmost vertical arrow. Furthermore, the entire forward curve forecasts the entire forward curve. So, second point from the left, in 2010 the market forecast that today's one-year forward rate would be about 4.2%, not the tenth of a percent or so that we see. If the forward rate forecast is correct, today's forward rate curve should lie exactly on the 2010 forward curve. (Proving that is another nice problem set question for finance classes.)

So, from the perspective of 2010, we have seen quite a large, surprise, downward shift of the "market expectations" in the forward curve.  It has been a great few years for holders of long term bonds.

However, beware: What goes down can come up again. To those who say "interest rates are low, the market doesn't see trouble coming, why worry?" I think the graph shows the magnitude of interest rate risk. And risk goes in both directions.

So, I'm still doom and gloomy. But the danger we face is unpredictable. Large debts mean that the government is out of ammunition, didn't pay the insurance bill, the fire extinguishers are empty, we are prone to a run or a sovereign debt "bubble" bursting (I hate that word, but I think it conveys the spirit), choose your anecdote. We could have a Japanese decade. It could be February 1994, when spreads and recent history looked a lot like today's. Or we could be on the edge of Greece, whose interest rates were pretty low once upon a time as well. The market forecast interpolates between these options.

The first principle of portfolio maximization is risk management, not prognostication. There remains a lot of risk.