science

TONAR

TONAR 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 TONAR rather than just read about it. In short: Tokyo Overnight Average Rate (TONA rate or TONAR) or Japanese Yen Uncollateralized Overnight Call Rate (Japanese: 無担保コールO/N物レート) is an unsecured interbank overnight interest rate and reference rate for Japanese yen. Mutan rate and TONA rate are the same things.

Key takeaways

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

Reference excerpt

Tokyo Overnight Average Rate (TONA rate or TONAR) or Japanese Yen Uncollateralized Overnight Call Rate (Japanese: 無担保コールO/N物レート) is an unsecured interbank overnight interest rate and reference rate for Japanese yen. Mutan rate and TONA rate are the same things.

History Japanese yen uncollateralized overnight call market started in July 1985. Since December 28, 2016, the Bank of Japan has recommended the TONA rate as the preferred Japanese yen risk-free reference rate. TONA rate is recommended as a replacement for Japanese yen LIBOR, which was phased out at the end of 2021, and Euroyen TIBOR, which will be terminated at the end of 2024.

Target rates

TONA Compounded Benchmarks TONA Averages TONA Averages are derived from the daily compounded TONA rate. The terms are 30day, 90days, and 180 days. TONA Index Assets when 100 was invested in TONA on June 14, 2017.

References

External links Daily TONA rate - Bank of Japan Monthly TONA rate - Bank of Japan TONA Averages & TONA Index - QUICK Corp

Worked examples

Example 1 — a first encounter with TONAR

Start with the simplest possible case. Write down what TONAR 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 TONAR 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 TONAR 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 TONAR

In research: TONAR 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 TONAR 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: TONAR is common in secondary-school and first-year university syllabi. It links to neighbouring topics Interest rates, Reference rates, so understanding it makes those chapters shorter.
In everyday life: Look for TONAR 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 TONAR in 20 minutes

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

Frequently asked questions

What is TONAR in simple terms?

Why does TONAR 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 TONAR?

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 TONAR.