The yield curve and recession signals

The yield curve compares the interest rates the US Treasury pays on bonds of different maturities, from a few months to thirty years. Its shape summarizes what bond investors collectively expect about future interest rates and economic growth. An inverted curve, where short-term yields are higher than long-term yields, has a long record of appearing before US recessions, which is why it gets so much attention. It is a useful signal and a poor stopwatch.

What the curve shows

A yield is the annual return an investor earns by holding a bond to maturity at its current price. If you are new to the idea, bond yields and prices explains why prices and yields move in opposite directions. Plot the yield of each Treasury maturity against its length and you get the curve.

• Normal (upward sloping). Longer maturities yield more than shorter ones. Investors usually want extra compensation for tying up money longer and for uncertainty about inflation and rates.
• Flat. Short and long yields are about equal.
• Inverted. Short-term yields are above long-term yields.

Two spreads are most often followed:

10-year minus 2-year spread = 10-year yield - 2-year yield
10-year minus 3-month spread = 10-year yield - 3-month yield

Example (illustrative numbers). If the 10-year yield is 4.0% and the 2-year yield is 4.6%, the 10-year minus 2-year spread is -0.6 percentage points, so the curve is inverted by that measure. If the 10-year yield were 4.5% and the 2-year yield 3.5%, the spread would be +1.0 and the curve would be upward sloping.

Why inversion happens

Short-term yields follow the policy rate set by the central bank closely, as described in interest rates and the Federal Reserve. Long-term yields reflect the market's average expectation of short rates over the bond's life, plus a premium for risk and time. When the central bank has raised short rates high enough to restrain the economy, and investors expect rates to fall later as growth or inflation weakens, long yields can end up below short yields. In that sense, inversion is a market bet that today's tight policy will not last.

There is also a plausible mechanism through lending. Banks typically borrow at short-term rates and lend at longer-term rates. When the curve is inverted, that margin shrinks, which can make banks more cautious about extending credit. Less credit can slow the economy. This is one reason economists see the curve as more than just a mirror of expectations, although the strength of this channel is debated.

The track record, and its limits

In the United States, inversions of the curve, especially the 10-year minus 3-month spread, have preceded most recessions since the 1960s, with occasional false alarms. The lead time has varied widely, from several months to well over a year. That variability is the key limit. Researchers have built formal recession-probability models on the spread, and the Federal Reserve Bank of New York publishes one, but the models give probabilities, not dates.

Recessions in the US are officially dated by the National Bureau of Economic Research (NBER). It defines a recession as a significant decline in economic activity spread across the economy and lasting more than a few months. The NBER announces its dates well after the fact, sometimes many months later, so the label "recession" is rarely available in real time. A popular rule of thumb, two consecutive quarters of falling GDP, is not the official definition. For the data behind these calls, see GDP, CPI, PMI and jobs data.

Other recession signals

No single signal is reliable on its own, which is why analysts look at several together:

• Unemployment dynamics. The Sahm rule flags a possible recession when the three-month average of the unemployment rate rises by 0.5 percentage points or more above its low over the previous 12 months.
• Manufacturing surveys. Purchasing managers' indexes below 50 indicate contraction in the surveyed sector.
• Initial jobless claims. A sustained rise in weekly claims can show labor-market weakening early.
• Credit conditions. Wider spreads between corporate and Treasury yields signal that lenders are more worried about defaults.

What it means for stocks

The yield curve does not tell you when stocks will fall. Stock markets have at times kept rising for many months after an inversion, and at other times fell before it. Equity prices look ahead, and a recession that is already expected can be partly priced in. The curve also often steepens again as central banks cut rates, and recessions have frequently begun around or after that re-steepening, so a "normal" curve is not an all-clear. Read the curve as a change in the odds for the economy, which then feeds into corporate earnings expectations, rather than as a call on the market. For how markets behave across cycles, see bull and bear markets.

Common mistakes

• Treating inversion as a timer. The delay between inversion and recession has been long and uneven.
• Mixing up measures. The 10-year minus 2-year and the 10-year minus 3-month spreads can differ in sign and timing.
• Assuming causation is certain. The curve may signal conditions rather than cause them.
• Selling everything on a single headline. One indicator is not a portfolio plan.
• Forgetting false alarms. A good record is not a perfect one.

Where to see it on StocksXray

The Market Compass combines market-based signals into a Risk-on, Neutral, Cautious or Defensive gauge and places the economy in a regime quadrant. It is one way to see how markets are collectively pricing risk, and its hints describe past tendencies, not forecasts. The logic of regimes is covered in economic regimes and the Market Compass.

Key takeaways

• The yield curve plots Treasury yields across maturities; inversion means short yields exceed long yields.
• Inversion has preceded most US recessions since the 1960s, with false alarms and a variable lead time.
• It signals changed odds, not a date, and says little about when stocks will turn.
• Use it alongside labor, survey and credit indicators rather than alone.
• The NBER dates recessions, usually long after they begin.