Building Liquidity Exposure from Balance Sheet Cash Flows

Book: Financial Risk Management: Applications in Market, Credit, Asset and Liability Management and Firmwide Risk Authors: Jimmy Skoglund & Wei Chen ISBN: 978-1-119-13551-7

Once you accept that liquidity risk is about cash flows under stress, the next question is: where do those cash flows come from? This section of Chapter 6 builds the exposure from the ground up.

Balance sheet cash flows

Everything on the balance sheet generates or absorbs cash over time. The liquidity exposure analysis maps assets and liabilities to contractual and behavioral cash flow schedules under crisis scenarios.

Asset inflows

Loans pay principal and interest on schedules, but prepayment behavior changes everything. Mortgages prepay faster when rates fall. Under stress, delinquencies slow inflows and defaults create losses instead of cash.

Investment assets mature or pay coupons. Sale of securities generates liquidity, but market value may be depressed in stress.

Funding and liability outflows

Deposits are the big one. Retail deposits are “sticky” until they are not. The chapter models withdrawal scenarios where a fraction of stable deposits leave over the stress horizon. Wholesale funding is more flight-prone.

Committed facilities (credit lines the bank has issued) can be drawn when borrowers face their own liquidity crunch. Unused facility limits become outflows under stress.

Market funding (commercial paper, interbank loans) may not roll. Maturity walls create cliff effects.

Off-balance-sheet derivative flows

Derivatives generate margin calls and collateral flows. A bank’s trading book can demand large liquidity postings when markets move, even if the underlying positions are hedged.

Behavioral uncertainty

The hardest part is not the contractual schedule. It is behavior.

• Will depositors run?
• Will facility borrowers draw down?
• Will the bank’s own counterparties increase margin requirements?

Each assumption shifts the net cash outflow curve. Regulators prescribe behavioral factors for standardized liquidity tests. Internal stress tests use bank-specific models calibrated to historical experience.

Market effects

Funding costs rise in stress (wider spreads, shorter tenors offered). Asset values fall, reducing the counterbalancing capacity of the hedging portfolio. Fire-sale discounts mean selling a bond for 85 cents on the dollar when you need par.

Combining risk and finance views

Liquidity analysis needs both the risk team’s scenario assumptions and the finance team’s balance sheet data. Loan-level cash flows, deposit categories, facility utilization, and treasury funding positions all feed one consolidated forward liquidity exposure curve.

Disagreements between ALM (asset-liability management) and risk on deposit stickiness or prepayment speeds are common. The book pushes for explicit scenario documentation so everyone works off the same stress definition.

Growth assumptions matter

The chapter compares business growth models: balance sheet grows with GDP, grows with market share targets, or stays flat under stress. Each choice changes the forward funding gap. Aggressive growth under benign assumptions creates hidden liquidity need when stress hits and growth plans collide with market closure.

Loan prepayment and new origination assumptions interact. In a rate shock, prepayments may spike while new lending slows. The net effect on cash flows is not obvious without a full simulation.

Derivative and trading book flows

For banks with large derivatives books, variation margin and initial margin flows can dominate short-term liquidity needs. A rates shock can trigger collateral calls across hundreds of counterparties on the same day. Liquidity exposure analysis must include CSA terms, netting sets, and the lag between call and settlement.

My take

This is the unglamorous core of liquidity risk management. Not ratios on a dashboard, but thousands of cash flow lines with behavioral overlays.

If your liquidity model treats all deposits as stable because they have been stable for five years, you are making the same mistake banks made before 2007. The chapter’s Northern Rock example is the cautionary tale.

The combine-risk-and-finance-view section is a political map as much as a technical one. Whoever owns deposit runoff assumptions owns the liquidity result. Document them.

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