Finance Formulas

Fixed Income

core

Money Duration & PVBP

Builds onModified Duration — if this page feels steep, start there.

MoneyDur=ModDur×P,PVBP=MoneyDur×0.0001MoneyDur = ModDur \times P, \qquad PVBP = MoneyDur \times 0.0001

Reading the notation

ModDurModDur
modified duration: the position's % price change per unit of yield change
PP
the position's full market value (price times holdings)
MoneyDurMoneyDur
money (dollar) duration: dollars of value change per unit of yield change
0.00010.0001
one basis point written as a decimal — the trader's natural increment
PVBPPVBP
price value of a basis point (a.k.a. DV01): dollars gained or lost per 1bp yield move

Why it must be true

Modified duration answers in percentages; a risk manager's phone call demands dollars. Money duration is the conversion: multiply the percentage sensitivity by the position's market value, and you get dollars of P&L per unit of yield move.

Scale it to the trader's natural increment — one basis point (0.01%) — and you have the PVBP ("price value of a basis point," also DV01): the dollars this position gains or loses when yields tick once. Desks live in this unit: "I'm running $40k of DV01" says exactly how much a one-tick rate move costs, position sizes are set by it, and hedges are built by matching it — equal and opposite PVBPs cancel.

The derivation

Start from modified duration's definition as a percentage response:

ΔPPModDurΔy\frac{\Delta P}{P} \approx -ModDur \cdot \Delta y

Multiply through by the position's value PP to convert percent into dollars:

ΔP(ModDur×P)MoneyDurΔy\Delta P \approx -\underbrace{(ModDur \times P)}_{MoneyDur} \cdot \Delta y

Set Δy\Delta y to one basis point (0.00010.0001):

PVBP=ModDur×P×0.0001PVBP = ModDur \times P \times 0.0001

Duration, money duration and PVBP are one fact in three units: percent per yield, dollars per yield, dollars per basis point.

When to reach for it

Converting duration into dollar terms for a specific position — sizing rate risk, setting limits, or matching a hedge in DV01.

Listen for

money duration / dollar durationPVBP / DV01 / price value of a basis pointdollar impact of a one-basis-point changehedge ratio by matching DV01

Back-of-the-envelope

Estimate it in your head first — then the calculator only confirms.

  • Decimal shuffle: PVBP = ModDur × P × 10⁻⁴. A $1m position with duration 5 → 5 × 1{,}000{,}000 / 10{,}000 = $500 per bp. Divide by ten thousand, done.

  • Scale check: PVBP is SMALL relative to the position (basis points are small). If your 'PVBP' is 1% of the position, you computed money duration instead.

  • Linear in both inputs: double the position or double the duration, double the PVBP — hedge ratios are just PVBP ratios.

Traps in applying it

  • Quoting money duration when PVBP was asked (off by the 10⁻⁴ factor) — the most common slip.
  • Using the face value instead of the market value of the position.
  • Forgetting the sign convention in use: PVBP is quoted as a positive magnitude, but yields up means value DOWN for a long.

Limits & criticisms

PVBP inherits duration's linearity: exact for one basis point, drifting for large moves where convexity takes over — a 100bp scenario is not 100 PVBPs. It also prices only parallel shifts of the position's own yield; curve twists need key-rate PVBPs, and the measure must be recomputed as prices and durations drift — yesterday's DV01 is stale after a big rally.

Where it came from

Dollar-based risk measures grew up on 1970s–80s bond desks, when Volcker-era volatility made "how many dollars do we lose per basis point?" the daily survival question — dealers hedging with the new Treasury futures needed DV01-matching to size the hedge. Today PVBP is the native language of every rates desk, risk report and futures hedge ratio: regulators aggregate bank rate-risk in DV01 terms, and swap desks quote hedges by matching it.

One identity, 2 questions

The exam can hide any variable. Each face below is the same equation solved for a different unknown — drill them separately.

Money duration

MoneyDur=ModDur×PMoneyDur = ModDur \times P

The unit conversion: percent-per-yield into dollars-per-yield — duration priced for THIS position.

Drill this face →

Dollars per tick

PVBP=ModDur×P×0.0001PVBP = ModDur \times P \times 0.0001

The desk's unit: what one basis point costs. Hedging = finding the position with equal and opposite PVBP.

Drill this face →

On the BA II Plus

Worked example: A portfolio of $500,000.00 carries modified duration 9.5. Compute its DV01 (PVBP).

  1. 1.9.5 [×] 500000 [=]money duration first
  2. 2.[×] 0.0001 [=]scale to one basis point

$475.00