The Yield Curve, Explained: Why an Inversion Gets So Much Attention

Few charts get as much attention from economists as the Treasury yield curve. It has a long record as a recession warning, and when it “inverts”, it makes headlines. Here is what it is and how much weight to give it.

What the yield curve is

The yield curve plots the yields on U.S. Treasury securities against their maturities, from one month out to 30 years. Normally it slopes upward: investors demand a higher yield to lend for ten years than for three months, to compensate for tying up their money longer and for the risk that inflation or rates change along the way. This extra compensation is called the term premium.

What short and long rates reflect

• Short-term yields (three months to two years) track the Federal Reserve’s policy rate and what markets expect the Fed to do in the near future.
• Long-term yields (ten to 30 years) reflect expectations for the average short-term rate over the coming decade, plus the term premium. These expectations depend on long-run growth and inflation.

Inversion

The curve inverts when short-term yields rise above long-term yields. This usually happens when the Fed has raised short rates to fight inflation, while investors expect that policy to slow the economy enough that rates will have to come down later. In effect, the bond market is betting that today’s tight policy will not last.

The spreads people watch

Two measures are standard:

• 10-year minus 2-year (“2s10s”), the most widely quoted in markets.
• 10-year minus 3-month, favored in research by the Federal Reserve Bank of New York, which publishes a recession-probability model based on it.

A negative number means the curve is inverted.

The track record

The 10-year/3-month spread inverted before each U.S. recession since the late 1960s, usually with a lead time of roughly six months to two years. That is an impressive record for a single indicator, and it explains the attention.

But there are important caveats:

1. Few observations. There have only been eight or so recessions in that period. A handful of hits does not make a law of nature.
2. The timing is vague. A lead of anywhere from six to 24 months is not much help for timing investments.
3. False alarms happen. The curve inverted in the mid-1960s without a recession following, and the deep inversion that began in 2022 lasted more than two years without the recession that many forecasters had expected arriving on the usual schedule.
4. The market structure has changed. Large central-bank bond purchases and changes in the term premium can flatten or invert the curve for reasons that have less to do with recession expectations.

Un-inversion

Some analysts argue that the more dangerous moment is not the inversion but the re-steepening that follows, when the Fed starts cutting short-term rates because the economy is weakening. Historically, recessions have often begun after the curve had already turned positive again. Whether this pattern holds is debated; the honest answer is that the yield curve is one input among many.

How to use it

Treat the yield curve as a summary of what the bond market expects about future Fed policy and growth — useful information, and a reason to look closer at other indicators such as unemployment claims, the jobs report and corporate earnings. Do not treat it as a timer for buying or selling stocks: even when the signal eventually proved right, stocks often rose for many months after the curve first inverted.

You can see the current curve, and the history of both spreads, on the Federal Reserve Bank of St. Louis’s free FRED database (series T10Y2Y and T10Y3M).