Executive summary
- ALM manages four objectives simultaneously: stability of earnings, protection of economic value, adequacy of liquidity and sufficiency of capital.
- Actions that stabilise net interest income over the next twelve months often increase sensitivity of economic value, and the reverse is equally true.
- Behavioural assumptions — particularly non-maturity deposit repricing and prepayment — usually drive results more than the rate scenarios applied.
- In insurance, ALM is dominated by liability duration, guarantees and the reinvestment risk that arises when liabilities outlast available assets.
- The governance question is which objective is prioritised, over what horizon, and who has authority to accept the resulting exposure.
The four objectives and why they conflict
A balance sheet can be optimised for any one of four things. Earnings stability asks that net interest income, or the equivalent insurance margin, does not swing materially with market movements. Value protection asks that the present value of assets less liabilities is insensitive to the yield curve. Liquidity adequacy asks that obligations can be met as they fall due under stress. Capital sufficiency asks that resources remain above requirement after adverse outcomes.
These pull in different directions. Funding long-dated fixed-rate assets with short-dated deposits raises current earnings and increases economic-value sensitivity. Extending liability duration through term funding protects liquidity and reduces earnings. Holding a large high-quality liquid asset buffer improves survival horizons and depresses return on equity. There is no configuration that maximises all four.
Earnings versus value
The clearest tension is between net interest income sensitivity and economic value of equity sensitivity. Earnings measures are short-horizon and accrual-based; value measures are full-horizon and discounted. A repricing profile that looks well matched on an earnings basis can carry substantial value exposure sitting beyond the earnings horizon. Institutions that manage only what appears in next year's income statement accumulate exposure they are not measuring.
Measurement in banks and insurers
Bank ALM is normally organised around repricing gap analysis, net interest income simulation, economic value of equity sensitivity, liquidity cash-flow ladders and funds transfer pricing. The Basel framework for interest-rate risk in the banking book sets out standardised shock scenarios and supervisory outlier tests, which serve as a common reference point rather than as a complete measurement system.
Insurance ALM starts from the liability side. Long-dated guarantees, participating features and options held by policyholders determine what the asset portfolio has to achieve. Where liabilities extend beyond available asset maturities, reinvestment risk cannot be hedged away and must be capitalised or shared. Solvency frameworks require the interaction to be assessed explicitly through matching, duration and convexity analysis.
| Dimension | Bank banking book | Life insurer |
|---|---|---|
| Dominant driver | Deposit behaviour and repricing profile | Liability duration and embedded guarantees |
| Primary earnings measure | Net interest income sensitivity | Investment margin and new-business strain |
| Primary value measure | Economic value of equity | Own funds and surplus sensitivity |
| Key structural constraint | Liquidity outflow under stress | Availability of matching long-dated assets |
Behavioural assumptions carry most of the model risk
Contractual cash flows are observable. Behavioural cash flows are estimated, and the estimates dominate the results. The repricing beta and effective duration assigned to non-maturity deposits typically move economic value sensitivity more than any plausible change in the rate scenario. Prepayment speeds on fixed-rate lending, early surrender on savings contracts and drawdown on committed facilities have the same character.
- Models estimated on a long period of stable or falling rates will understate sensitivity in a sharp tightening cycle.
- Depositor behaviour changes with the availability of digital alternatives, which shortens the effective stability of balances that historical data suggests are sticky.
- Assumption sets should be accompanied by a sensitivity range, and the range should be shown to the committee that approves the strategy.
Governance: the asset and liability committee
ALM decisions are consequential and reversible only slowly. The asset and liability committee is the mechanism through which the trade-off between objectives is made deliberately. Effective committees share several characteristics: they receive earnings and value measures together rather than in alternate months, they see the behavioural assumptions and their sensitivity, they are given a limited number of decisions rather than a large pack of monitoring, and they record the rationale for the position taken.
- Limits should cover both earnings and value dimensions, with defined escalation when either is approached.
- Funds transfer pricing should charge business lines for the liquidity and interest-rate risk they create, otherwise the balance-sheet cost is invisible where it originates.
- Hedging strategy should be documented against a stated objective; hedging to reduce earnings volatility and hedging to protect value require different instruments.
Practical example
Consider a simplified bank funding a portfolio of ten-year fixed-rate loans with retail current accounts. Suppose management assigns the deposits an effective repricing duration of four years based on historical stability. Under that assumption, a parallel rate rise produces a moderate economic-value loss because the asset and assumed liability durations partially offset.
Now suppose the assumed duration is reduced to eighteen months to reflect faster depositor migration to higher-paying alternatives. Nothing about the contractual balance sheet has changed, yet the measured value sensitivity increases substantially and the position may breach an internal limit. The point of the illustration is that the assumption, not the market, drove the change — which is why the assumption deserves board-level visibility and independent validation.
Limitations and caveats
- ALM measures are conditional on behavioural models whose parameters are estimated from periods that may not resemble the conditions being tested.
- Parallel-shift scenarios are analytically convenient but rarely representative; non-parallel and basis movements can produce larger losses.
- Economic value measures assume positions can be held or unwound at modelled values, which may not hold in a stressed market.
- Regulatory references evolve. Any framework should be checked against the current official text of the applicable standard before reliance.
Conclusion
Asset and liability management is not a reporting exercise. It is the standing decision about how much earnings volatility, value sensitivity, liquidity risk and capital consumption an institution is prepared to carry, and in what combination.
The technical work — gap analysis, simulation, behavioural modelling — exists to make that decision informed. When ALM reporting grows while the number of decisions it supports stays constant, the discipline has drifted from its purpose.
References
- Interest rate risk in the banking book — standards — Basel Committee on Banking Supervision, 2016
- Guidelines on the management of interest rate risk and credit spread risk arising from non-trading book activities — European Banking Authority, 2022
- Solvency II Directive 2009/138/EC — European Commission, 2009
Author bio
Jonas Mohamed Osman Abdelghafour, known as Yonas Osman is an actuary, FRM and financial risk professional specialising in banking, insurance, model risk, capital modelling and quantitative risk management.