Unseen Levers

markets · Curated Lever · 5 min

Why does a bond's price fall when interest rates rise?

An old fixed payment must become cheaper to compete with a new higher yield.

The intuitive answer

The issuer automatically cuts the bond's promised payment.

In 30 seconds

A fixed-rate bond keeps promising the same cash flows. When new bonds offer higher yields, investors will buy the old bond only at a lower price that makes its unchanged payments competitive.

Read the full explanation

The unseen lever

Market price adjusts so the present value and yield of fixed future cash flows reflect current required returns.

  1. triggerMarket interest rates rise
    increases
  2. mechanismNew bonds offer higher returns
    decreases
  3. mechanismThe old bond's fixed payments look less attractive
    decreases
  4. outcomeIts price falls until its yield is competitive

The deeper explanation

The short answer is the start, not the whole story.

A fixed-rate bond keeps promising the same cash flows. When new bonds offer higher yields, investors will buy the old bond only at a lower price that makes its unchanged payments competitive.

Common overstatements

A holder who keeps a default-free bond to maturity may still receive promised cash flows, but the opportunity cost and market value have changed.

Where the answer stops

Floating-rate and inflation-linked bonds respond differently from plain fixed-rate bonds.

Concepts that unlock it

Coupon

A bond's scheduled interest payment.

Yield

Return implied by a bond's price and promised cash flows.

Present value

Today's value of future payments discounted at a required return.

Duration

A measure of how sensitive a bond's price is to interest-rate changes.

What if?

What if the bond matured tomorrow instead of in twenty years?

Fewer distant payments need repricingPrice sensitivity is much smallerReinvestment happens sooner

Check your understanding

Can you move the mechanism?

Question 1 of 2

Why must an old 2% bond fall when comparable new bonds yield 4%?

Question 2 of 2

Which is normally more rate-sensitive?

Evidence and limits

What supports this answer?