Repo Interest, Consideration and Repayment Calculations - Article

Introduction

A repo is economically a secured borrowing transaction.

The repo seller or borrower:

• transfers eligible securities in the first leg;

• receives funds;

• uses those funds for the agreed repo period; and

• repays the funds plus repo interest in the second leg.

The repo buyer or lender sees exactly the opposite cash flow.

For CAIIB numerical questions, the central calculation is therefore:

First-leg funds → Repo interest → Second-leg repayment

The current IIBF CAIIB BFM syllabus includes Money Market Products under Module C – Treasury Products.

RBI continues to require banks undertaking repo and reverse-repo transactions to follow the Repurchase Transactions (Repo) (Reserve Bank) Directions, 2018, as amended from time to time.

Learning Objectives

After studying this topic, you should be able to:

• identify the first-leg cash consideration in a repo;

• calculate repo interest using the correct day-count convention;

• determine the second-leg repayment amount;

• derive the repo rate when consideration amounts are given;

• distinguish clean price, accrued interest, and cash consideration;

• understand the effect of collateral haircut on the funds available;

• distinguish repo interest from coupon income; and

• avoid common CAIIB numerical mistakes.

Basic Numerical Structure of a Repo

Every standard repo calculation can be understood through three values:

First-Leg Consideration

This is the amount of cash received by the repo seller or borrower.

RBI describes the first-leg consideration as the amount borrowed by the seller of the security.

Repo Interest

This is the borrowing cost for using the funds during the repo period.

Second-Leg Consideration

This is the amount paid by the borrower when the securities are repurchased.

In the normal numerical structure:

Second-leg consideration = First-leg consideration + Repo interest

RBI accounting guidance states that the difference between the consideration amounts of the first and second legs represents repo interest.

Repo Interest Formula

Repo Interest = First-Leg Cash Consideration × Repo Rate × Repo Tenor ÷ 365

Use the repo rate in decimal form and the actual number of days in the repo period.

Refer to the Formula Section for a detailed explanation, variables, and solved examples.

RBI's illustrative repo calculations use the Actual/365 convention for repo interest because repo is a money-market transaction.

What the Formula Means

Repo interest depends directly on three factors:

• amount borrowed;

• repo rate; and

• number of days.

Therefore:

Higher borrowing amount → Higher repo interest

Higher repo rate → Higher repo interest

Longer repo tenor → Higher repo interest

provided the other factors remain unchanged.

Actual/365 Convention

The Indian money market follows the Actual/365 day-count convention.

This means:

• numerator = actual number of days in the repo period;

• denominator = 365.

RBI explicitly identifies Actual/365 as the Indian money-market convention and uses it in repo-interest illustrations.

This becomes particularly important where a question contains both:

• accrued interest on a coupon-bearing Government security; and

• repo interest.

The two calculations may use different day-count conventions.

Second-Leg Repayment

Once repo interest has been determined, the repayment amount can be calculated.

Second-Leg Cash Consideration = First-Leg Cash Consideration + Repo Interest

This gives the amount payable by the repo borrower at maturity, subject to treatment of any intervening cash flows under the applicable transaction structure.

Refer to the Formula Section for a detailed explanation, variables, and solved examples.

RBI's repo illustrations follow this basic approach, with the second-leg cash consideration exceeding the first-leg cash consideration by the repo interest.

Borrower Perspective

For the repo seller:

• First leg = cash inflow

• Repo interest = borrowing expense

• Second leg = cash outflow

Lender Perspective

For the reverse-repo buyer:

• First leg = cash outflow

• Repo interest = lending income

• Second leg = cash inflow

The amount of repo interest is the same transaction amount viewed from opposite accounting perspectives.

Deriving the Repo Rate

A CAIIB question may provide:

• first-leg consideration;

• second-leg consideration; and

• repo tenor;

and ask for the repo rate.

First determine repo interest:

Repo Interest = Second-Leg Consideration − First-Leg Consideration

This identifies the financing income or expense embedded between the two transaction legs.

Refer to the Formula Section for a detailed explanation, variables, and solved examples.

Then annualise that return:

Repo Rate (%) = [Repo Interest ÷ First-Leg Consideration] × [365 ÷ Repo Tenor] × 100

This derives the annualised repo rate from the two cash consideration amounts.

Refer to the Formula Section for a detailed explanation, variables, and solved examples.

This reverse calculation is useful because numerical questions do not always directly provide the repo rate.

First-Leg Consideration

A common mistake is to assume that:

Face value of securities = amount borrowed

This is not necessarily correct.

The first-leg consideration depends on the value at which the collateral transaction is undertaken and, where relevant, accrued interest and haircut arrangements.

RBI guidance provides that the first leg should be contracted at prevailing market-related prices.

For exam purposes, identify whether the question gives:

• face value;

• market or clean price;

• accrued interest;

• dirty price;

• haircut; or

• actual cash consideration.

If the first-leg cash consideration is directly given, use that amount for calculating repo interest unless the question clearly requires another adjustment.

Coupon-Bearing Security as Repo Collateral

When the security offered under repo is a coupon-bearing bond, its quoted market price may be a clean price.

The actual settlement consideration may also include accrued coupon interest.

Conceptually:

First-Leg Cash Consideration = Clean Price Amount + Accrued Interest

This determines the cash settlement amount where the market quotation excludes accrued coupon.

Refer to the Formula Section for a detailed explanation, variables, and solved examples.

RBI's illustrative repo calculations for coupon-bearing securities add broken-period accrued interest to the market price to obtain the first-leg cash consideration.

Clean Price and Dirty Price

This distinction can appear inside repo questions.

Clean Price

The quoted market price of a coupon-bearing bond excluding accrued interest.

Accrued Interest

Interest accumulated from the previous coupon date to the settlement date.

Dirty Price

The amount including both:

Clean Price + Accrued Interest

Therefore, when a question provides a clean price and accrued interest separately, do not calculate repo interest on the clean price alone if the relevant first-leg cash consideration includes both.

Bond Accrued Interest vs Repo Interest

These two forms of interest must not be confused.

Accrued Interest on the Security

This belongs to the coupon-bearing security.

It represents coupon accrued over part of the coupon period.

Repo Interest

This belongs to the financing transaction.

It represents the cost of borrowing funds for the repo period.

These calculations serve completely different purposes.

RBI's illustrative methodology uses 30/360 for broken-period interest on the bond and Actual/365 for repo interest.

This distinction is a high-value CAIIB examination area.

Repo Using Treasury Bills

A Treasury Bill has no coupon.

Therefore, there is no coupon accrued interest to add in the same manner as for a dated coupon-bearing security.

The repo calculation focuses primarily on:

• T-Bill market value or relevant first-leg consideration;

• repo rate;

• repo tenor; and

• second-leg consideration.

RBI guidance recognises that discounted instruments such as Treasury Bills do not have coupons and treats their discount separately from repo interest.

This leads to an important distinction:

T-Bill discount ≠ Repo interest

The T-Bill discount belongs to the underlying security.

Repo interest belongs to the borrowing transaction.

Effect of Haircut

Some secured funding questions may specify a haircut.

A haircut reduces the collateral value recognised for lending purposes.

If the question states that funding is based directly on collateral market value after haircut:

Funds Available = Collateral Market Value × (1 − Haircut Rate)

This determines the funding amount after applying the prescribed collateral-value reduction.

Refer to the Formula Section for a detailed explanation, variables, and solved examples.

Therefore:

Higher haircut → Lower amount available against the same collateral

Once the actual cash amount advanced has been established, repo interest is calculated on the relevant funded amount according to the terms of the question.

Important Numerical Trap

Do not automatically deduct a haircut when the question already gives the first-leg cash consideration.

Doing so may apply the haircut twice.

Read carefully whether the amount provided is:

• collateral market value; or

• actual cash lent.

Repo Calculation Flow

For most CAIIB questions, use this sequence:

Step 1: Identify the Repo Perspective

Determine whether the party is:

• repo borrower/seller; or

• reverse-repo lender/buyer.

The numerical amount may be identical, but the interpretation as expense or income changes.

Step 2: Find the First-Leg Cash Consideration

Use the directly provided consideration where available.

If not, identify whether it must be derived from:

• clean price;

• accrued interest;

• market value; or

• haircut-adjusted collateral value.

Step 3: Identify the Repo Tenor

Use the actual number of days from the first leg to the reversal date.

Step 4: Apply the Repo Rate

Use the rate applicable to the repo transaction.

Do not substitute:

• bond coupon rate;

• T-Bill yield; or

• RBI policy repo rate

unless the question expressly makes that rate the contracted repo rate.

Step 5: Calculate Repo Interest

Apply the Actual/365 money-market convention.

Step 6: Determine Second-Leg Consideration

Add repo interest to the relevant first-leg cash consideration.

Step 7: Perform a Reasonableness Check

For a normal positive repo rate:

Second-leg cash consideration > First-leg cash consideration

If not, check your calculation.

Intervening Coupon During the Repo Period

A slightly more advanced case arises when a coupon payment on the collateral security falls within the repo period.

RBI states that where a coupon is received by the repo buyer during the repo period, it should be passed to the repo seller, because the second-leg consideration does not include such intervening cash flows.

This reflects the economic principle that the repo seller retains the economic interest in the underlying security during the repo period.

For CAIIB, remember:

Coupon on collateral ≠ lender's repo income

The lender's financing return is the repo interest.

Repo Interest as Income and Expense

The same repo interest has different meaning for the two parties.

Repo Seller / Borrower

Repo interest is:

Interest expenditure

because the party has borrowed funds.

Reverse-Repo Buyer / Lender

Repo interest is:

Interest income

because the party has provided funds.

RBI accounting guidance recognises the difference between first- and second-leg consideration as repo interest income for the lender and repo interest expenditure for the borrower.

Market Repo Rate vs RBI Policy Repo Rate

Another numerical trap is assuming that every repo must use the RBI policy repo rate.

That is incorrect.

A market repo is entered into at the agreed market repo rate applicable to that transaction.

RBI's policy repo rate belongs to RBI's monetary-policy framework.

Therefore, if a CAIIB question states:

A bank enters into a market repo at 6.20%

then 6.20% is the rate to use, regardless of whether RBI's prevailing policy repo rate is different.

Practical Interpretation of Results

A numerical answer should make economic sense.

Repo Interest Increases When:

• first-leg funding increases;

• repo rate increases; or

• repo period increases.

Repo Interest Decreases When:

• funding amount decreases;

• repo rate decreases; or

• repo period becomes shorter.

Haircut Increases

For a given collateral value:

Borrowing capacity falls.

Reverse Repo

The same calculated repo interest becomes income for the lender rather than expense.

These relationships allow you to check an answer even before relying on the exact arithmetic.

Calculator Discipline for CAIIB

Repo calculations are normally simple once the correct inputs are identified.

Use this checklist before calculation:

Amount: Is it face value, market value, dirty value, or actual first-leg consideration?

Rate: Is it coupon rate, repo rate, yield, or policy rate?

Time: Is the tenor given in actual days?

Convention: Use Actual/365 for repo interest under the RBI money-market convention.

Haircut: Has it already been applied?

Perspective: Is the answer interest income or interest expense?

Repayment: Have you added repo interest to the first-leg consideration?

This prevents most avoidable errors.

CAIIB Exam Focus

Repo interest is calculated on the first-leg cash consideration.

Do not automatically use face value of collateral.

Repo interest follows the money-market Actual/365 convention in RBI's illustrative treatment.

Second-leg consideration normally equals first-leg consideration plus repo interest.

The difference between first- and second-leg consideration represents repo interest.

Repo seller = borrower = repo interest expense.

Reverse-repo buyer = lender = repo interest income.

Bond coupon rate and repo rate are different.

The coupon belongs to the security; the repo rate belongs to the financing transaction.

Accrued bond interest and repo interest may use different day-count conventions.

A haircut affects the amount that can be borrowed against collateral.

Do not apply a haircut twice.

A coupon received during the repo period belongs economically to the repo seller and is passed through according to RBI treatment.

Market repo rate and RBI policy repo rate are not automatically the same.

Common Exam Traps

Trap 1: Calculating Repo Interest on Face Value

Incorrect when the actual first-leg consideration is different.

Interest is based on the relevant cash borrowed.

Trap 2: Using the Security Coupon Rate as Repo Rate

Incorrect.

The coupon rate belongs to the collateral security. Repo rate represents the cost of secured borrowing.

Trap 3: Using 360 Days for Repo Interest

Incorrect under RBI's illustrated Indian money-market convention.

Repo interest uses Actual/365.

Trap 4: Assuming Accrued Interest and Repo Interest Are the Same

Incorrect.

Accrued interest relates to the bond coupon. Repo interest relates to financing.

Trap 5: Treating Repo Interest as Income for the Borrower

Incorrect.

For the repo seller/borrower, it is an expense.

For the reverse-repo lender, it is income.

Trap 6: Subtracting Repo Interest from First-Leg Consideration

Normally incorrect for repayment.

For a positive repo rate:

Second-leg consideration = First-leg consideration + Repo interest

Trap 7: Applying Haircut to an Amount Already Identified as Cash Consideration

This may double-count the haircut.

First establish exactly what the supplied amount represents.

Trap 8: Using Original Security Maturity as Repo Tenor

Incorrect.

Repo tenor is the period between the two repo legs, not the maturity of the collateral security.

A ten-year Government bond can be used in an overnight repo.

Trap 9: Using RBI's Policy Repo Rate Automatically

Incorrect.

Use the contracted repo rate specified for the transaction.

Trap 10: Treating Coupon Received During Repo as Extra Repo Income

Incorrect.

An intervening coupon on the underlying security is treated separately from repo financing income.

Trap 11: Assuming Reverse Repo Needs a Different Interest Formula

Incorrect.

It is the same transaction viewed from the lender's side. The arithmetic remains the same; the income/expense interpretation changes.

Trap 12: Rounding Every Intermediate Step

This can cause the final answer to differ.

Keep sufficient decimal precision and round only as required at the end.

Memory Technique

Remember the repo numerical sequence as C-R-D-I-R:

• C – Consideration borrowed

• R – Repo rate

• D – Days

• I – Interest

• R – Repayment

And remember:

365 for Money

Repo is a money-market transaction, so repo-interest calculations use the Actual/365 convention in RBI illustrations.

For the two parties:

Repo = Borrow → Interest Expense

Reverse Repo = Lend → Interest Income