DeskPrep
EXCELintermediate~50 min

PnL Attribution Sheet

Rebuild each desk's PnL from its drivers, reconcile to the front-office figure and isolate the position whose PnL doesn't explain.

The scenario

You're in the middle office and the daily PnL has to be signed off. Each desk's result comes in as a single number from the front office, but your job is to rebuild it from its drivers — market move, carry, fees, new trades — and prove the two figures reconcile. Today one position doesn't explain: the book carries a small unexplained residual, and you need to isolate which desk it sits on before sign-off.

Where this shows up

Rebuilding PnL from its drivers and reconciling to the front office is the signature product-control / middle-office exercise at banks of this type.

investment-bank product controlmiddle-office PnLfund finance / valuations

Firms such as Goldman Sachs, Morgan Stanley, Barclays.

DeskPrep is not affiliated with, endorsed by, or sponsored by any named firm. Firm names are used for illustrative, educational purposes only and do not imply that these materials are official assessments of, or are connected with, those firms.

Task brief

README.md
# PnL Attribution Sheet (Middle Office)

**Role relevance:** Middle-office / product-control take-home.
**Estimated time:** 50 minutes  ·  **Difficulty:** Intermediate  ·  **Format:** Excel (.xlsx)

## What you are given
- `pnl_attribution_sheet_starter.xlsx` — a **Brief** tab, a **Formula Help** tab and a **PnL** tab with each desk's driver breakdown and the front-office figure. Amber cells are yours to complete.

## What you must deliver
1. Build each position's **MO PnL** by summing its drivers (market, carry, fees, new-trade)
2. Compute the **residual** against the front-office figure per position
3. Identify the position with the largest unexplained residual with a **lookup**
4. A *PnL-by-driver* chart and a one-line explanation of the residual

Your tasks

  1. 01Build each position's MO PnL by summing its drivers (market, carry, fees, new-trade).
  2. 02Compute the residual against the front-office figure for every position.
  3. 03Identify the position with the largest unexplained residual using a lookup, not by eye.
  4. 04Total the book, chart PnL by driver, and explain in one line what the residual most likely is.

How you're assessed

MO Total per position (driver sum)3 pts
Residual vs front office2 pts
Locate the break with a lookup2 pts
Book totals1 pt
Chart + plausible explanation of the residual2 pts
Total10 pts

The full points-based mark scheme is included with the pack.

What you'll learn

  • What 'PnL explain' is and why every day's PnL must reconcile to its drivers before sign-off.
  • Why an unexplained residual is investigated even when it's small — small today, systematic tomorrow.
  • How to isolate a break to a single desk instead of burying it in a book total.

Study alongside