WSU Lexicon: Fixed Income

Inverted Yield Curve

An inverted yield curve is a downward-sloping term structure in which short-maturity yields exceed long-maturity yields on comparable-credit bonds, typically government securities. It usually reflects expectations of falling future short-term rates, often tied to policy easing during an anticipated slowdown.

Its normal counterpart is an upward-sloping curve; the flat curve sits between them.

The entry

Why Long Yields Fall Below Short Yields

A long-term yield is, in essence, an average of expected future short-term rates plus a term premium. Inversion therefore requires the expected path of short rates to decline sharply enough to overcome whatever premium investors demand for holding duration. This normally happens late in a tightening cycle: policy rates are already restrictive, and market participants price cuts within the next one to two years.

The arithmetic is visible in implied forward rates. If the one-year spot rate is 5.00% and the two-year spot rate is 4.50%, the one-year rate one year forward solves from the condition that one plus the two-year rate, squared, equals one plus the one-year rate multiplied by one plus the forward rate. That gives roughly 4.00%. Whenever the curve slopes downward, forward rates lie below current spot rates over the inverted segment.

The entry

Measuring Inversion: Which Spread, Which Curve

Practitioners quote inversion as a spread between two benchmark points. The 2s10s spread (ten-year yield minus two-year yield) is the most cited, while the three-month to ten-year spread is favoured in econometric work because the short leg tracks the policy rate closely. These measures can disagree: the curve may invert between two and ten years while the very front end still slopes upward, producing a humped shape rather than a uniformly downward-sloping one.

The object being measured also matters. Par yield curves, spot (zero-coupon) curves and forward curves invert at different times and by different amounts, because coupon effects and compounding shift the mapping between them. A spot curve that is only mildly downward-sloping can imply forward rates that are deeply inverted, since forwards amplify the slope.

The entry

Consequences Across Markets and Balance Sheets

Banks fund short and lend long, so a sustained inversion compresses net interest margins and tends to tighten credit supply, which is one channel through which inversion may help cause the slowdown it predicts. Leveraged carry positions financed in the repo or money markets become uneconomic when the financing rate exceeds the asset yield, forcing deleveraging in mortgage and corporate bond portfolios.

For bond investors, rolldown reverses. On an upward-sloping curve, a bond's yield falls as it ages and shortens, generating price gains if the curve is unchanged. On an inverted curve the ageing bond rolls toward higher yields, so the rolldown component of return is negative and cash or short maturities may dominate on a horizon-return basis unless yields actually decline.

The entry

What the Candidate Must Be Able to Execute

Expect to move fluently between spot rates and forwards: bootstrap zero rates from par or coupon bond prices, derive an implied forward rate from two spot rates, and state that a downward-sloping spot curve necessarily produces forwards below spot. You should also be able to explain inversion under each term-structure theory, noting that pure expectations attributes it entirely to anticipated rate declines, while liquidity preference requires an even larger expected decline because a positive term premium must be offset.

On the portfolio side, know the directional logic of curve trades. A flattener profits as long yields fall relative to short yields; a steepener benefits from the re-steepening that typically accompanies actual policy easing, often driven by the front end falling faster than the long end.

Common trap

“An inverted curve means investors expect interest rates to rise.”

The opposite. Under the expectations view, long yields are averages of expected future short rates plus a term premium. Long yields sitting below short yields implies the market expects short rates to fall, usually as central banks ease into weakening growth.

In practice

US 2s10s inversion, 2022–2024

As the Federal Reserve raised policy rates aggressively against inflation, the US 2-year Treasury yield rose above the 10-year in mid-2022 and stayed there into 2024: the longest sustained 2s10s inversion in the modern data record.

Candidates ask

Questions on this term

Does an inverted yield curve always signal a recession?No. Inversion has preceded most postwar US recessions, but lead times vary from months to roughly two years, and false signals occur. Suppressed term premia from asset purchases or strong foreign demand can invert the curve without a downturn.
Which spread should be used to judge inversion: 2s10s or 3m10y?Both are legitimate. The 2s10s spread is the market's headline measure and reacts quickly to shifts in expected policy. The three-month to ten-year spread anchors the short leg near the actual policy rate and has historically performed slightly better in recession-forecasting models. They can send conflicting signals when the very front end remains upward-sloping, so serious analysis looks at the whole curve rather than a single spread.
If the curve is inverted, why not simply hold short-dated bonds for the higher yield?That captures more income today but leaves you exposed to reinvestment risk. The inversion itself is the market pricing lower short rates ahead, so maturing short paper is expected to roll into a worse yield. Longer bonds lock in a lower yield now but carry the duration that generates capital gains if rates do fall. The correct comparison is total expected return over the investment horizon, not current yield.

Related entries

Forward RateA forward rate is an interest rate set today for borrowing or lending over a specified period that begins at a future date.
RecessionA recession is the contraction phase of the business cycle: a significant, broad-based decline in economic activity that persists for more than a few months, visible in falling real output, employment, income, and spending across many sectors of the economy..
Term Structure of Interest RatesThe term structure of interest rates is the relationship between yield and time to maturity for bonds of identical credit quality and currency.
Yield CurveThe yield curve is a plot of yields to maturity against time to maturity for bonds of one issuer or credit class that are otherwise identical in currency, coupon structure, and liquidity.

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Inverted Yield Curve

Its normal counterpart is an upward-sloping curve; the flat curve sits between them.