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Zero interest-rate policy

Zero interest-rate policy is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Zero interest-rate policy rather than just read about it. In short: Zero interest-rate policy (ZIRP) is a macroeconomic concept describing conditions with a very low nominal interest rate, such as those in contemporary Japan and in the United States from December 2008 through December 2015 and again from March 2020 until March 2022 amid the COVID-19 pandemic. ZIRP is considered to be an unconventional monetary policy instrument and can be associated with slow economic growth, deflat…

Zero interest-rate policy — main illustration
Zero interest-rate policy — illustration

Key takeaways

  • Zero interest-rate policy belongs to science; place it in that map before memorising details.
  • Learn the definition first, then one example that makes the definition concrete.
  • Connect Zero interest-rate policy to a quantity you can measure, compute or draw — that is where exam questions come from.
  • Reproduce the core statement of Zero interest-rate policy from memory before moving on to harder problems.

Reference excerpt

Zero interest-rate policy (ZIRP) is a macroeconomic concept describing conditions with a very low nominal interest rate, such as those in contemporary Japan and in the United States from December 2008 through December 2015 and again from March 2020 until March 2022 amid the COVID-19 pandemic. ZIRP is considered to be an unconventional monetary policy instrument and can be associated with slow economic growth, deflation and deleverage. ZIRP could also describe an interest-free economy.

Overview Under ZIRP, the central bank maintains a 0% nominal interest rate. The ZIRP is an important milestone in monetary policy because the central bank is typically no longer able to reduce nominal interest rates. ZIRP is very closely related to the problem of a liquidity trap, where nominal interest rates cannot adjust downward at a time when savings exceed investment. However, some economists—such as market monetarists—believe that unconventional monetary policy such as quantitative easing can be effective at the zero lower bound. Others argue that when monetary policy is already used to the maximal extent, governments must be willing to use fiscal policy to create jobs. The fiscal multiplier of government spending is expected to be larger when nominal interest rates are zero than they would be when nominal interest rates are above zero. Keynesian economics holds that the multiplier is above one, meaning government spending effectively boosts output. In his paper on this topic, Michael Woodford finds that, in a ZIRP situation, the optimal policy for government is to spend enough in stimulus to cover the entire output gap. Chris Modica and Warren Sulmasy find that the ZIRP policy follows from the need to refinance a high level of US public debt and from the need to recapitalize the world's banking system in the wake of the 2008 financial crisis.

Zero lower bound The zero lower bound problem refers to a situation in which the short-term nominal interest rate is zero, or just above zero, causing a liquidity trap and limiting the capacity that the central bank has for inflation targeting. This problem returned to prominence with Japan's experience during the 1990s and more recently with the American subprime crisis. Paul Krugman, Michael Woodford, and Milton Friedman argued that a zero nominal interest rate presents no problem for monetary policy, as a central bank can increase the monetary base only if it continues buying bonds.

See also

References

Further reading Eggertsson, Gauti B.; Woodford, Michael (2003). "The Zero Bound on Interest Rates and Optimal Monetary Policy". Brookings Papers on Economic Activity. 2003 (1): 139–211. CiteSeerX 10.1.1.603.7748. doi:10.1353/eca.2003.0010. JSTOR 1209148. S2CID 153895795. {{cite journal}}: Cite uses deprecated parameter |citeseerx= (help)

External links Monetary Policy Alternatives at the Zero Bound: An Empirical Assessment Fed Funds Rate: Turning Japanese, I Really Think So Nominal Interest Rates: Less Than Zero? Macroeconomics Wiki: Zero Lower Bound Problem

Illustrations

Zero interest-rate policy: Japan bonds  Inverted yield curve in 1990 
Zero interest-rate policy starting in 1999[1]  
Negative interest policy started in 2016[2]
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  20 year
  10 year
  5 year
  2 year
  1 year
Japan bonds Inverted yield curve in 1990 Zero interest-rate policy starting in 1999[1] Negative interest policy started in 2016[2] .mw-parser-output .legend{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .legend-color{display:inline-block;min-width:1.25em;height:1.25em;line-height:1.25;margin:1px 0;text-align:center;border:1px solid black;background-color:transparent;color:black}.mw-parser-output .legend-text{}  30 year   20 year   10 year   5 year   2 year   1 year
Zero interest-rate policy: Japan money supply and inflation (year over year)
  M2 money supply
  Inflation
Japan money supply and inflation (year over year)   M2 money supply   Inflation
Zero interest-rate policy: US inflation rates
US inflation rates

Worked examples

Example 1 — a first encounter with Zero interest-rate policy

Start with the simplest possible case. Write down what Zero interest-rate policy claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Zero interest-rate policy before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Zero interest-rate policy ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Zero interest-rate policy

In research
Zero interest-rate policy appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry
Engineering practice reuses Zero interest-rate policy in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom
Zero interest-rate policy is common in secondary-school and first-year university syllabi. It links to neighbouring topics Interest rates, Monetary policy, so understanding it makes those chapters shorter.
In everyday life
Look for Zero interest-rate policy outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.
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How to study Zero interest-rate policy in 20 minutes

  1. Read the reference excerpt below once, without taking notes.
  2. Close the page and write down what Zero interest-rate policy means in your own words.
  3. Compare your version with the excerpt and mark what you missed.
  4. Work through the three examples above with pen and paper.
  5. Explain Zero interest-rate policy out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Zero interest-rate policy in simple terms?

Zero interest-rate policy (ZIRP) is a macroeconomic concept describing conditions with a very low nominal interest rate, such as those in contemporary Japan and in the United States from December 2008 through December 2015 and again from March 2020 until March 2022 amid the COVID-19 pandemic. ZIRP…

Why does Zero interest-rate policy matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Zero interest-rate policy?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Zero interest-rate policy.

Tags

  • Interest rates
  • Monetary policy

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