Bond Yields Explained: Why One Number Moves Every Other Market

If you had to follow a single number to understand what markets are doing, it would not be a stock index. It would be the yield on the ten-year government bond.

That yield sits underneath almost everything else. It shapes what a company is worth, what a currency is worth, what gold is worth relative to an interest-bearing alternative, and what a mortgage costs. When it moves sharply, other markets rearrange themselves around it.

What a yield is

A government bond is a loan. You hand over capital, receive fixed interest payments called coupons, and get the principal back at maturity.

The yield is the annualised return you earn if you buy at today's price and hold to maturity. It is not the coupon. The coupon is fixed at issue and never changes; the yield changes constantly because the price does.

Why price and yield move in opposite directions

This is the part that confuses people, and it resolves with one example.

A bond pays 3 units of interest a year and returns 100 at maturity.

• Buy it at 100. You earn 3 on 100, a yield of 3%.
• Interest rates in the economy rise, and new bonds now pay 5. Nobody wants yours at 100.
• The price falls to about 60. The buyer still receives 3 a year, but on 60 that is a yield of 5%.

The cash flows never changed. Only the price did, and the yield is simply that fixed cash flow expressed against the current price. Price down, yield up. Always, mechanically.

This is why "bonds sold off" and "yields rose" describe the same event.

The three components inside a yield

A long-term yield is not one decision. It decomposes into three:

1. Expected future short-term rates. What the market thinks the central bank will do over the life of the bond.
2. Expected inflation. Lending for ten years means being repaid in money that will buy less. Investors demand compensation.
3. Term premium. Extra return demanded for tying capital up and bearing the risk that the first two estimates are wrong.

When a yield moves, it is worth asking which component moved. A rise driven by growth expectations is a very different signal from a rise driven by inflation fear or by a buyers' strike in the bond market.

Real yields: the version that matters

The real yield is the nominal yield minus expected inflation. It is the return measured in purchasing power.

Nominal yield	Expected inflation	Real yield
4.5%	2.0%	+2.5%
4.5%	4.5%	0.0%
3.0%	5.0%	−2.0%
1.0%	2.5%	−1.5%

A negative real yield means you are guaranteed to lose purchasing power by holding the bond to maturity. That sounds irrational, and investors still accept it — institutions with mandates, banks meeting capital requirements, central banks holding reserves.

Real yields explain a great deal that nominal yields do not. Gold pays no income, so its main disadvantage against a bond is the income foregone. When real yields are deeply negative, that disadvantage disappears, and gold has historically performed well. When real yields rise sharply, gold has historically struggled. It is one of the more durable relationships in macro.

The yield curve

Plot yields against maturity — 3 months, 2 years, 10 years, 30 years — and you get the yield curve. Its shape carries information.

Shape	What it looks like	Usual interpretation
Upward sloping	Long yields above short	Normal. Growth expected, term premium positive
Flat	Similar across maturities	Transition, uncertainty about the path of rates
Inverted	Short yields above long	Markets expect rate cuts, usually because they expect weakness
Steepening	Long rising faster than short	Growth or inflation expectations rising

Inversion draws attention because it has preceded most US recessions since the 1960s. It is worth being careful with that claim: the lag between inversion and recession has ranged from months to more than two years, the signal has been wrong at least once, and the sample of recessions is small. It is a signal worth knowing about, not a timing tool.

How yields reach other markets

Equities. A share is a claim on future earnings, and valuing future earnings means discounting them to today. The discount rate is anchored on the government bond yield. Raise the yield and the present value of distant earnings falls. This hits companies whose value sits far in the future — typically high-growth technology — much harder than companies earning cash now.

Currencies. Capital moves toward higher risk-adjusted returns. If US yields rise while European yields do not, holding dollars pays comparatively more, and the dollar tends to strengthen. What matters is the differential between two countries, not the level in one.

Gold and other non-yielding assets. As above: the cost of holding them is the income given up.

Mortgages and corporate borrowing. Long-term government yields are the base on which mortgage and corporate borrowing rates are set, with a credit spread added on top. This is the channel through which bond markets reach households.

What to watch, in practice

• The 10-year yield as the general reference for long-term rates.
• The 2-year yield, which tracks expectations for central bank policy closely.
• The 2s10s spread (10-year minus 2-year) as the standard curve measure.
• Inflation-linked yields, which give the real yield directly rather than by estimate.
• The pace of a move. A 20 basis point move in a week is ordinary. The same move in an afternoon means something has changed.

All of these are published free by the US Treasury, the Bank of England and central bank data services.

The bottom line

Bond yields are the price of money over time, and almost every other asset is priced relative to that. A shift in yields is rarely a story about bonds alone — it is the market revising its view on growth, inflation or policy, and everything else re-pricing to match.

You do not need to trade bonds to benefit from watching them. You need to understand that when someone asks why shares fell on a day with no company news, the answer is frequently sitting in the yield curve.

This article is educational and is not financial advice.