What the yield curve is

The US government borrows for every length of time, from three months to thirty years. The yield curve is simply a line through those borrowing rates, short on the left, long on the right.

Normally the line slopes upward. Lending your money for ten years ties it up longer and exposes you to more inflation risk than lending for two, so investors demand more for it. That extra yield is the term premium, and a rising curve is the healthy default.

Two spreads summarise the shape, and both are published daily by the Federal Reserve Bank of St. Louis:

SpreadWhat it isLatest, Oct 9
10s2s, series T10Y2Y10-year yield minus 2-year yield+0.44 points
10s3m, series T10Y3M10-year yield minus 3-month yield+0.99 points

Both are positive today: the 10-year yields 5.22%, the 2-year 4.75% and the 3-month 4.23%. The 10-year is at its highest level since June 2007.

What an inversion means

An inverted curve is one where short rates are higher than long rates, so the spread turns negative. It happens when the central bank holds short rates high to fight inflation while bond investors, looking further ahead, expect that tight policy to slow the economy enough that rates will have to come down later.

In plain terms, an inversion is the bond market saying: the Fed is squeezing hard now, and we think it will have to reverse. That is why it is watched as a recession warning. It is not a law of economics, it is a record of what investors expected, and its reputation comes entirely from its history.

The track record

Here is every 10s2s inversion lasting more than three weeks since 1978, and the month the next US recession began according to the National Bureau of Economic Research.

InversionLengthDeepestRecession beganLead time
Aug 1978 to May 1980622 daysnegative 2.41Feb 198018 months
Sep 1980 to Jul 1982672 daysnegative 1.70Aug 198111 months
Dec 1988 to Nov 1989328 daysnegative 0.45Aug 199020 months
May 1998 to Jul 199862 daysnegative 0.07none within 2 yearsno signal
Feb 2000 to Dec 2000330 daysnegative 0.52Apr 200114 months
Dec 2005 to Jun 2007525 daysnegative 0.19Jan 200825 months
Aug 2019, three days3 daysnegative 0.04Mar 20207 months
Apr 2022 to Sep 2024888 daysnegative 1.08none through Sep 202654 months and counting

Five substantial inversions before 2022 and a brief one in 2019, followed by six recessions, with lead times of 11 to 25 months for the substantial ones. That is the record that made the curve famous. Two footnotes matter: the 1998 dip was too brief and shallow to count, and the 2019 signal was three days long and the recession that followed was caused by a pandemic, which no bond market predicted.

Then the last row. The 2022 inversion was the longest on record, 888 days, and the deepest since 1981. By the old rule a recession was due by 2024 at the latest. The National Bureau of Economic Research has dated none through September 2026, 54 months after the inversion began.

Why the signal may have failed this time

Nobody can prove it, but three explanations are widely discussed.

The inversion came from the short end. The Fed lifted short rates from near zero to over 5% in about a year, the fastest pace in four decades. The curve inverted because short rates leapt, not because long-term growth expectations collapsed, which is a weaker recession message.

Households and companies had locked in cheap money. Fixed-rate mortgages and long corporate bonds taken out in 2020 and 2021 shielded much of the economy from higher short rates for years.

Heavy government borrowing pushed the long end up. Large deficits keep long yields higher than growth alone would justify, and a curve that is steepening for that reason says little about recession.

The honest summary is that the yield curve is a record of expectations, and expectations can be wrong. A signal that was right six times and then early by at least 30 months is still informative. It is no longer a timing tool.

What Bitcoin did through the longest inversion

Bitcoin has only existed through two inversions, so there is not much history to measure. The 2022 to 2024 episode is the one that matters, and it is instructive.

MomentDateBitcoin
Curve invertsApr 1, 2022$46,283
Low during the inversionNov 21, 2022$15,781
High during the inversionMar 13, 2024$73,072
Curve turns positiveSep 5, 2024$56,180
LatestOct 10, 2026$83,097

Across the full inversion Bitcoin gained about 21%, but the path went through a 66% fall to the November 2022 low and then a 363% rise to the March 2024 high. Since the curve turned positive it has added another 48%.

Two lessons. First, the inversion told you nothing useful about Bitcoin's direction: the worst crash and one of the best rallies both happened inside it. Second, the much-discussed danger moment for stocks, the re-steepening after an inversion ends, has so far coincided with a Bitcoin rise rather than a fall. One episode is not a pattern, and we are not presenting it as one.

How to read the curve yourself

Use both spreads. Many economists, including researchers at the New York Fed, prefer 10s3m to 10s2s because the 3-month rate tracks Fed policy more directly. When they disagree, treat the signal as weaker.

Watch duration, not a single day. The 2019 inversion lasted three days. Meaningful signals have lasted months.

Look at why it moves. A curve steepening because long yields rise on deficit worries means something different from one steepening because short rates fall in a rate-cutting panic.

The data is free. FRED series T10Y2Y, T10Y3M, DGS10 and DGS2 update every business day.