The current US economic expansion started in July 2009 and is already much longer than the post-war average, although still below the 10-year record duration set in the 1990’s, while closing in on the no.2 spot, set at 106 months in the 1960’s. A near term downturn is not inevitable but history suggests is likely at some point over the next few years. Forecasters are poor at predicting recessions, and so there is interest in other potential signals. Equity markets generally turn down ahead of the real economy but they can and do fall without that precipitating a decline in GDP, so there is a risk of a false signal. The relationship between short term interest rates and long rates (the yield curve) is another indicator of note, and in the US has proven remarkably accurate ahead of the last seven downturns. Specifically, a yield curve inversion ( 10 year yields below 2 year yields or as some prefer, 3- month rates) has proven to be an excellent signal of a US recession a year or so ahead.
Why the success as a signal? Longer term bond yields carry a risk premium and are therefore generally higher than short rates, and may also be influenced by specific demand/supply factors at different maturities. For example, banks generally buy shorter term bonds, while pension funds seek much longer maturities. Expectations about the path of short term rates over the period are the most important factor, however, which in the US amounts to expectations about the Fed’s monetary policy and inflation. If policy is tightened in response to a booming economy or above target inflation longer term rates tend to rise, albeit by less than the move in short rates (the curve flattens) and may eventually invert if the market believes that short rates have peaked and will eventually start falling . The inverted yield curve may also help precipitate a downturn because it dampens margins for the banking sector (banks borrow short and lend long)
The US yield curve is not currently inverted but it has flattened appreciably; the 2-10 year spread has fallen from a peak of 260 basis points in late 2013 to just under 60 now, having started the year at 135.The recent pace of flattening has prompted much market debate particularly as short rates are still very low by historical standards.
The Fed is widely forecast to raise short rates again as early as December , and has signalled that it expects to tighten further in 2018, yet 10-year yields have fallen in absolute terms over the past month and are well below the highs in yield recorded earlier in the year.Maturing Treasuries are no longer being fully reinvested and, all things equal, the Fed’s decision to steadily reduce its holdings of bonds might be expected to push yields up. Some argue that issuance is shifting towards the shorter end of the yield curve, so supporting longer dated paper, which in any case is still in strong demand as a ‘safe’ asset and such assets are relatively scarce as central banks elsewhere are still buying.
A bigger factor may simply be that the market is convinced, at least for now, that US inflation will continue to disappoint the Fed and remain below the 2% target, so implying that short rates will not rise to the extent the FOMC expect. The current core inflation rate is only 1.3% ( the consumption deflator ex food and energy) and was last (briefly) above 2% in early 2012. Most Fed governors believe that inflation will eventually start to accelerate as wages belatedly respond to the extremely low unemployment rate, but that view is not universally shared. Indeed, the minutes from the most recent FOMC meeting point to growing doubts as to whether sub-target inflation is indeed ‘transitory’.
Yield curve models are currently giving a low probability of recession in 2018 it has to be said ( the New York Fed’s model indicates around 10%) but the yield curve certainly bears watching given the recent trend.