Bond Math — Time Value, Price & YTM
y = annual yield · f = compounding frequency · n = number of periods
When coupon = yield → price = par (100). Yield rises → price falls. Always.
The single constant discount rate applied to all future cashflows such that PV = market price. Assumes reinvestment of all coupons at YTM (rarely true in practice).
Bloomberg quotes clean price. You pay the dirty price at settlement.
Key Takeaways
- Price ↑ when yield ↓ — always and in every market
- YTM = IRR = the "true" yield blended across all cashflows
- Discount factors are the building blocks — everything else follows
- You pay dirty price; clean price is just the quote convention
Interest Rate Risk — Duration, Convexity & DV01
Weighted average time until you receive your money back. Zero-coupon bond: MacDur = maturity. Coupon bond: MacDur < maturity (early coupons pull it forward).
Yields fall: actual price gain > duration predicts (second-order bonus). Yields rise: actual price loss < duration predicts. Convexity is always positive for straight bonds — a gift to holders.
⚠ Negative convexity: Callable bonds and MBS — the upside is capped (bond gets called away when rates fall)
| Convention | Used For | Denominator |
|---|---|---|
| ACT/ACT | US Treasuries | Actual days in year |
| ACT/360 | Money markets, most swaps, corporate | 360 |
| ACT/365 | UK Gilts | 365 |
| 30/360 | US corporate bonds | Assumes 30-day months |
Key Takeaways
- Duration = speed; convexity = acceleration of price change
- DV01 is how traders size and hedge positions — "P&L per basis point"
- Convexity is a free gift for straight bond holders; negative convexity is a tax for MBS/callable holders
- Day count matters — ACT/360 vs ACT/365 creates meaningful differences on large positions
Money Markets — T-Bills, SOFR, Repos & FRAs
| Rate | Type | Use |
|---|---|---|
| SOFR | Secured overnight | New USD risk-free benchmark; repo-based; $1T+/day |
| EFFR (Fed Funds) | Unsecured overnight | Fed policy target; interbank; OIS floating leg |
| LIBOR | Historical panel | Retired June 2023; replaced by SOFR/SONIA/ESTR/TONAR |
| TED Spread | LIBOR − T-Bill | Bank credit risk gauge; spiked to 450bps in 2008 |
Cash borrower sells bonds to cash lender with agreement to buy them back at a higher price. Effectively: borrow cash using bonds as collateral.
GC (General Collateral) repo: any eligible bond; rates near risk-free.
Special repo: specific bond in high demand → lower repo rate (lender accepts less to obtain that specific bond — reveals which bonds are heavily shorted).
Haircut: bonds posted worth more than cash received (e.g., $100 bonds → $98 cash = 2% haircut).
Swap where floating leg = overnight rate compounded daily. OIS rate = market's expectation for the AVERAGE overnight rate over the swap's term.
LIBOR-OIS spread: The interbank stress thermometer. Near zero normally; 350bps+ in the GFC.
Key Takeaways
- T-Bills: discount pricing means the quoted rate understates true yield
- SOFR = new USD risk-free rate; secured by Treasuries; $1T/day in volume
- Repo = the leverage engine; special repos reveal short demand for specific bonds
- OIS = purest measure of Fed policy expectations across the curve
- LIBOR-OIS spread = stress gauge; "special" repo = short interest signal
The Yield Curve — Par, Spot, Forward; Carry, Rolldown & Trades
| Curve | Definition | Bloomberg |
|---|---|---|
| Par | Yield on bonds priced at 100 (coupon = yield) | WIR<GO> |
| Spot/Zero | Yield on zero-coupon bonds; derived via bootstrapping | ICVS<GO> |
| Forward | Implied rate for a future period; F(1y1y) = [(1+Z₂)² / (1+Z₁)] − 1 | FWCM<GO> |
Steepener: Long front end, short long end. Profits when long end sells off more than front end.
Flattener: Short front end, long long end. Profits when front end rises more than long end (Fed hikes).
Butterfly: Long belly, short wings (or vice versa). Isolates the curve shape vs parallel shift.
2s10s spread: 10Y − 2Y yield. Inversion (negative) historically signals recession.
Key Takeaways
- Par < Spot < Forward — always on a normal (upward-sloping) curve
- Carry + rolldown = compensation for duration risk, not a free lunch
- Inverted 2s10s = historically reliable recession precursor
- Every curve trade must be DV01-neutral to isolate shape exposure from parallel shift
- Bloomberg: CARY<GO> (carry/rolldown), FWCM<GO> (forward rates), BFLY<GO> (butterfly)
Futures — Eurodollar, Treasury Note/Bond Futures & CTD
DV01 = $25 per contract per 1bp. Organized in Packs (4 consecutive quarters) by color: White/Red/Green/Blue (WRGB).
| Ticker | Contract | Eligible Maturity |
|---|---|---|
TU/ZT | 2Y T-Note | 1Y9M to 2Y |
FV/ZF | 5Y T-Note | 4Y2M to 5Y3M |
TY/ZN | 10Y T-Note | 6Y6M to 10Y |
US/ZB | T-Bond | 15Y+ |
WN/UB | Ultra T-Bond | 25Y+ |
Quoted in 32nds: 131-29 = 131 + 29/32 = 131.90625. Physically settled.
The futures short delivers the cheapest bond. Bloomberg DLV<GO> sorts by implied repo — top = CTD.
Rule: yields > 6% → longest eligible bond tends to be CTD; yields < 6% → shortest.
Key Takeaways
- Eurodollar futures = $25 DV01; 100 − rate pricing; WRGB color packs
- Treasury futures standardize all bonds to a theoretical 6% coupon via Conversion Factor
- Invoice Price is what you pay/receive at delivery
- CTD = highest implied repo rate = best cash-and-carry for the short
- Bloomberg: DLV<GO> (CTD), FIHZ<GO> (horizon analysis)
Options on Futures — Greeks, MOVE Index & Vol Skew
| Greek | Measures | Sign for Long Options |
|---|---|---|
| Delta | Price change per unit futures move | Call: 0 to +1; Put: −1 to 0 |
| Gamma | Rate of delta change; highest ATM near expiry | Positive (long) |
| Vega | Sensitivity to implied volatility | Positive (long) |
| Theta | Time decay; erodes option value daily | Negative (long) |
Merrill Lynch Option Volatility Estimate. 1-month normalized implied vol on US Treasuries, weighted across 2Y/5Y/10Y/30Y. Bloomberg: MOVE Index.
High MOVE = rate uncertainty, Fed path unclear. Low MOVE = complacency.
MBS holders hate high MOVE (prepayment uncertainty drives up option cost).
Equities: Puts always more expensive than calls (left tail fear → negative skew, always).
Bonds: Skew direction FLIPS with the rate environment. In rising-rate environments: rate calls (bond puts) get more expensive. Near zero rates: floors are expensive. The "direction" of concern reverses — unlike equities.
Key Takeaways
- Options on Treasury futures = right to buy/sell the future at a set price
- MOVE = bond VIX; high = uncertainty; MBS managers watch this closely
- Bond skew is not a one-way street — direction depends on rate level and direction of fear
- Long straddle = long vol; buy when MOVE is low, expect a big move
- Bloomberg: OVME<GO> (options valuation), OMON<GO> (options monitor)
Bootstrapping the Yield Curve
Pattern: use known zeros to discount interim coupons; the last cashflow is the only unknown.
The forward curve embeds the market's implied rate expectations for every future period.
Why: par rate blends all coupons (early low-rate ones drag it down); zero must compound purely at the long-end rate; forward must exceed zero to make their average equal the zero rate.
Key Takeaways
- Bootstrapping: iterate maturity by maturity, using known zeros to strip prior coupons
- Zero rates are more precise for pricing — each cashflow discounted at its own rate
- Forward rates = market-implied expectations embedded in today's spot curve
- Derivation flow: Par → Spot/Zero → Forward → Forward Par
- Bloomberg: FWCM<GO> (forward matrix), ICVS<GO> (curve builder), FWCV<GO> (horizon curve)
Corporate Bonds — Structure, Types & Trading
If a company defaults, each layer is paid in full before the next gets anything. Senior secured = safest; equity = first to zero.
| Type | Description | Key Risk |
|---|---|---|
| Bullet | Fixed coupon, one maturity date | Pure duration + credit |
| Callable | Issuer can redeem early | Extension risk if not called; reinvestment risk if called |
| Puttable | Investor can sell back early | Reinvestment risk for investor (favorable) |
| Convertible | Bond + embedded equity call | Delta moves 0→1 as equity rises above conversion price |
| Perpetual | No maturity; coupon forever | Extension risk; issuer discretion on coupon |
| CoCo (AT1) | Converts/writes down at CET1 trigger | Binary: CET1 trigger → equity or zero |
| Name | Currency | Issuer |
|---|---|---|
| Yankee | USD | Non-US in US market |
| Eurodollar | USD | Non-US in European market |
| Samurai | JPY | Non-Japanese in Japan |
| Bulldog | GBP | Non-UK in UK market |
Key Takeaways
- Seniority is everything in default — know your position in the waterfall before you buy
- Callable bonds: higher yield, but capped upside (issuer calls when it hurts you most)
- CoCos: attractive yield, but the trigger can wipe you out without market warning (Standard Chartered 2017)
- Corporate bonds are OTC: check ALLQ<GO> for dealer axes; settlement T+2
- Convertible delta ranges 0 to 1: when deep in-the-money, it trades like equity
Credit Risk — G-Spread, I-Spread, Z-Spread, OAS & ASW
| Spread | Benchmark | Full Curve | Options | Tradeable |
|---|---|---|---|---|
| G-Spread | Government YTM | No | No | No |
| I-Spread | Swap YTM | No | No | No |
| Z-Spread | Zero swap curve | Yes | No | No |
| OAS | Zero swap curve | Yes | Yes (stripped) | No |
| ASW | SOFR/floating | Via discounting | No | Yes |
Uses stochastic rate tree (binomial). Higher vol assumption → option worth more → OAS smaller for callables.
For bullet bonds: OAS = Z-Spread always (no embedded option).
Buy corporate bond + enter fixed-to-float IRS (pay fixed coupon, receive SOFR/LIBOR + spread). The spread on the floating leg that makes NPV = 0 is the ASW.
What ASW MEANS: Bond + IRS = the bond's credit risk is now in the floating spread. It's the bond's credit risk expressed over the swaps curve, in tradeable form.
Key Takeaways
- Z-spread: most rigorous; uses full curve; but assumes no rate volatility
- OAS: Z-spread minus option value; correct for callable/puttable bonds
- For bullet bonds: Z-spread = OAS (always)
- ASW: only spread you can TRADE; how banks measure credit risk on funded positions
- Z-spread − OAS = value of the embedded option in basis points
- Extension risk: when an issuer fails to call → price drops sharply (market priced in the call)
Floating Rate Notes (FRNs)
Quoted Margin (QM) = at issuance. Discount Margin (DM) = secondary market equivalent. DM > QM → discount; DM < QM → premium.
| Type | When benchmark is set | Duration |
|---|---|---|
| In Advance (common) | Start of coupon period | Slightly higher (~next reset date) |
| In Arrears (rarer) | End of coupon period | Near zero |
Rates rise → coupon goes up → price stays near par ✓
Credit conditions tighten → DM widens → price drops ✗
Key Takeaways
- FRN duration ≈ 0 to next reset; they absorb rate moves through coupon adjustment
- FRNs are credit instruments: DM spread is what you're buying, not rate exposure
- March 2020 FLOT collapse proves: low duration does NOT mean low risk
- Day count (ACT/360 vs ACT/365) changes coupon meaningfully — verify before booking
- Bloomberg: YASN<GO> for OAS on floaters
TIPS — Treasury Inflation-Protected Securities
Deflation floor: principal cannot fall below par at maturity.
TIPS protect real value. They still expose you to:
- Real yield movements (GDP growth expectations, Fed policy, credit quality)
- If real yields RISE → TIPS price falls, just like any bond
TIPS = a bet on REAL RATES falling, not on inflation accelerating.
Key Takeaways
- TIPS: fixed rate on growing principal; principal floors at par at maturity (deflation protection)
- BEI = nominal − real; NOT a forecast; it's the equilibrium inflation rate for equal returns
- TIPS are real-rate instruments: real yields rise → TIPS price falls
- Long breakevens (long TIPS + short nominals) = bet actual inflation exceeds BEI
- 5Y5Y forward inflation swap = what the Fed watches for long-run inflation expectations
- Bloomberg: SWIL<GO> (inflation projections), SWPM-ILFX (ZC inflation swap)
Mortgage-Backed Securities (MBS)
| Term | Definition |
|---|---|
| Factor | Remaining principal as % of original (starts at 1.0) |
| WAC | Weighted Average Coupon (underlying mortgage rate) |
| WALA | Weighted Average Loan Age (months) |
| LTV | Loan-to-Value ratio (80% = standard conforming) |
| Day Delay | ~1.5 months between borrower payment and investor receipt |
| TPO | Third-party origination = more refi-aggressive pools |
Rates fall: Homeowners refi → MBS pays at par → price capped. You get cash back at the worst time (low rates).
Rates rise: Homeowners stay → loan extends → duration increases at the worst time ("extend-o-matic").
Only range-bound rates reward MBS holders with carry and no convexity headwind.
Sequential CMO: All principal flows to Tranche A first → B → C. A = shortest, most protected.
PAC (Planned Amortization Class): Pays off within a specific window across a PSA collar/band. "Busts" outside band.
IO Strips (Interest-Only): NEGATIVE DURATION. Rates rise → fewer prepayments → more interest payments → IO price RISES. Used as duration hedge.
Key Takeaways
- Agency MBS = no credit risk; 100% prepayment risk (you're short a call to every borrower)
- Negative convexity: MBS underperforms in both rallies AND sell-offs — only wins in range
- MOVE matters: high vol = expensive optionality = MBS OAS looks cheap but option cost is high
- Payups: premium pools (LLB, NY geo) prepay slower → worth paying a premium over TBA
- IO strips have negative duration — useful as a duration hedge for MBS portfolios
- CPR measures speed; PSA normalizes to a standard ramping curve
Interest Rate Swaps (IRS)
| Company | Fixed Rate | Floating Rate |
|---|---|---|
| A | 5% | LIBOR + 100 |
| B | 6% | LIBOR + 175 |
A borrows fixed (advantage), B borrows floating (advantage). Via a swap: A ends up paying LIBOR+15 (saves 85bps); B ends up paying 5.85% fixed (saves 15bps). Both parties win by exploiting comparative advantage.
KEY TAKEAWAY: "The swap rate you see quoted daily is the fixed coupon rate required to ensure the premium = 0. That is why the swap curve is called a par swaps curve."
| Era | Forward Rates | Discount Rate |
|---|---|---|
| Pre-2008 | LIBOR swap curve | LIBOR (same curve) |
| Post-2008 | LIBOR/swap curve (Bloomberg curve 23) | SOFR/OIS (Bloomberg curve 490) |
LCH shifted to SOFR discounting October 2020. Rationale: LIBOR reflects bank credit risk; SOFR is truly risk-free.
| XVA | Adjusts For |
|---|---|
| CVA | Counterparty credit risk (expected loss if they default) |
| DVA | Your own default risk (controversial) |
| FVA | Cost of funding uncollateralized exposure |
| MVA | Initial margin cost |
| KVA | Regulatory capital (RWA) cost |
Key Takeaways
- Payer = pays fixed = long duration (benefits from rates rising)
- Receiver = receives fixed = short duration (benefits from rates falling)
- Swap rate = par coupon — at inception, NPV = 0 for both sides
- Dual curve: forward rates from swap curve; discount from SOFR
- DV01 of swap ≈ DV01 of fixed leg; use to duration-hedge bond portfolios
- Dodd-Frank: most eligible swaps must clear via CCP (LCH, CME)
Other Swap Types — OIS, ASW, TRS, Basis Swaps & XCCY
IRS where floating leg = overnight rate (EFFR in USD, ESTR in EUR, SONIA in GBP, TONAR in JPY) compounded daily. Paid as single annual lump sum. OIS rate = market expectation for AVERAGE overnight rate over the swap term.
No principal exchange. Used to bet on Fed policy: pay fixed OIS if you think Fed will hike.
What ASW means: Bond + IRS = credit risk now in the floating spread. ASW = bond's credit risk over swaps curve, in tradeable form.
Receive total return of an asset (capital gain + income); pay floating financing rate (e.g., LIBOR+75bps). No principal exchange. Synthetic exposure without owning the asset.
Basis swaps price the value of LONGER-TERM funding certainty. The post-Lehman spike shows why the 3-month gap matters in stress.
Practical trade (March 2020, JPY-USD basis −57bps): Buy JGB at −0.22% yield → XCCY ASW → earn 1.1299% USD fixed. When domestic US 1Y bills yield 0.1654% — massive pickup.
Bloomberg: XCCY<GO> — global cross-currency basis spreads. Deeply negative = strong foreign USD demand.
| Currency | Spread | Interpretation |
|---|---|---|
| JPY | −26.25bps | Japanese investors pay to get USD |
| KRW | −71bps | Very strong Korean demand for USD |
| EUR | −6.50bps | EUR investors pay modest premium for USD |
| AUD | +16.50bps | USD investors pay to get AUD (rare) |
| CHF | −5.50bps | CHF investors pay to get USD |
Key Takeaways
- OIS = bet on Fed policy path; OIS rate = implied average overnight rate
- ASW = tradeable credit risk measure; the only spread you can actually transact
- TRS = synthetic total return; no ownership needed; Archegos used it for massive leverage
- Basis swaps: price the VALUE OF CERTAINTY — 6M funding > two 3M rollovers
- XCCY deeply negative = foreign investors desperate for USD (flight to dollar safety)
- XCCY value = f(USD swap rates, foreign swap rates, FX forward rates) — three drivers
Appendix — The Cheapest-to-Deliver Bond
| Rate Environment | CTD Tends To Be |
|---|---|
| Yields > 6% (futures convention) | Longest duration eligible bond |
| Yields < 6% | Shortest duration eligible bond |
CTD can SWITCH as rates move → creates switching risk in futures positions.
Key Takeaways
- Invoice Price = what the futures buyer pays for the delivered bond
- Gross Basis = cash price − invoice price (in 32nds); the short's "profit" on delivery
- Implied Repo = annualized cash-and-carry return; CTD = bond with highest implied repo
- DLV<GO> sorts deliverables by implied repo — top = CTD today
- CTD drives futures pricing; when CTD changes, the futures reprices
- Net Basis = Gross Basis − Carry = fairest value measure of the basis
Bloomberg Terminal Quick Reference
| Screen | Function | Chapter |
|---|---|---|
YAS<GO> | Yield & Spread Analysis (Z-spread, OAS, duration) | 9 |
ALLQ<GO> | All Quotes — dealer axes for corporates | 8 |
GC<GO> | G-Spread calculator | 9 |
SWPM<GO> | Swap Pricing/Manager — build any swap type | 13, 14 |
ASW<GO> | Asset Swap Spread calculator (quick) | 9, 14 |
ICVS<GO> | Curve Builder — construct custom yield curves | 7, 13 |
FWCM<GO> | Forward Rate Matrix — all forward rates | 4, 7 |
FWCV<GO> | Forward Curve horizon (shift to future date) | 7 |
CARY<GO> | Carry & Rolldown analysis | 4 |
BFLY<GO> | Butterfly trade structure | 4 |
DLV<GO> | Cheapest-to-Deliver screen (sorted by implied repo) | 5, 15 |
FIHZ<GO> | Fixed Income Horizon Analysis (hold period return) | 15 |
OVME<GO> | Options Valuation Manager | 6 |
OMON<GO> | Options Monitor | 6 |
MOVE Index | Bond market volatility index (bond's VIX) | 6 |
OSA<GO> | OAS Analysis | 9 |
YASN<GO> | OAS for floating rate notes | 10 |
SWIL<GO> | Inflation projections | 11 |
FWISUSS55 | 5Y5Y Forward Inflation Swap (Fed's favorite) | 11 |
TBA<GO> | TBA (To Be Announced) MBS market | 12 |
TBPF<GO> | TBA pricing and factors | 12 |
XCCY<GO> | Cross-Currency Basis Spreads (global) | 14 |
WIR<GO> | World Interest Rates (par curve comparison) | 4 |
WBF<GO> | World Bond Futures | 5 |
VCUB<GO> | Vol Cube | 6 |
SECF<GO> | Security Finder (bond search) | 8 |
PRPL<GO> | Principal/Price lookup | 9 |
CCRV<GO> | Credit Curve builder | 9 |
Formula Sheet
| Concept | Formula |
|---|---|
| Future Value | FV = PV × [1 + (y/f)]^n |
| Discount Factor | DF = 1 / [1 + (y/f)]^n |
| Bond Price | P = Σ [CF_t / (1+y)^t] |
| Modified Duration | ModDur = MacDur / (1 + y/f) |
| % Price Change | ΔP% ≈ −ModDur × Δy |
| PV01 | Price × ModDur / 100 |
| DV01 | PV01 × (Face / 100) |
| T-Bill Price | P = 100 − [disc_rate × days/360] |
| Carry | Yield − Repo Rate |
| Forward Rate | F(1y1y) = [(1+Z₂)² / (1+Z₁)] − 1 |
| Index Ratio (TIPS) | Reference CPI / Base CPI |
| Breakeven Inflation | BEI = Nominal Yield − TIPS Real Yield |
| 5Y5Y Forward Inflation | [(1+Z₁₀)^10 / (1+Z₅)^5]^(1/5) − 1 |
| Invoice Price (Futures) | Futures Price × CF + Accrued |
| Gross Basis | (Cash Price − Invoice Price) × 32 (in 32nds) |
| DV01-Neutral Ratio | N_short / N_long = DV01_long / DV01_short |
| OAS | Z-Spread − Option Value |
| PSA (after mo 30) | N PSA = N × 6% CPR |