BFF5916 · International Banking
Bank Financial Analysis
This is the calculation core of the unit — the engine that both the quizzes and the 30% group report run on. Everything hangs off one identity: Assets = Liabilities + Capital, where capital is a thin residual cushion, not a pile of cash. A bank funds a big loan book with deposits and only a sliver of equity, which is the source of both its high returns and its fragility. From the balance sheet and a short income strip you build a fixed ladder of ratios: net interest income (NII = interest income − interest expense) and the net interest margin (NIM = NII / assets, the lending spread only); return on assets (ROA = net profit after tax / assets, which captures interest AND fee margins net of costs and tax); leverage (the equity multiplier = assets / capital); and the DuPont leverage bridge ROE = ROA × assets/capital, which scales a tiny asset return into a large owner return. Round it off with the efficiency ratio (costs / revenue, lower is better) and asset quality (the NPL ratio, higher is worse). The exam's favourite question hands you a stylised balance sheet, asks you to build capital as a residual, then run the whole set and interpret it.
What this chapter covers
- 01The bank balance sheet — Assets = Liabilities + Capital
- 02Net interest income (NII) and the net interest margin (NIM)
- 03Return on assets (ROA) — total profitability
- 04Return on equity (ROE) and the DuPont leverage bridge
- 05Leverage (the equity multiplier) and why it cuts both ways
- 06The efficiency ratio (lower is better)
- 07Asset quality — the NPL ratio and provisions
Worked example: NIM, then ROE via the leverage bridge
- +2(a) NII = interest income − interest expense = 108 − 45 = $63m; NIM = NII / assets = 63 / 1,800 = 0.035 = 3.50% — the lending spread only.
- +1(b) ROA = NPAT / assets = 29.4 / 1,800 = 0.01633 = 1.63% — this captures the interest AND fee margins net of costs and tax (everything NIM leaves out).
- +1(c) Leverage (equity multiplier) = assets / capital = 1,800 / 150 = 12.0×.
- +1ROE via the bridge: ROE = ROA × assets/capital = 1.63% × 12.0 = 19.6%.
- +1Verify directly: NPAT / capital = 29.4 / 150 = 19.6% — the two routes agree, which is your proof you didn't flip a denominator.
Key terms
- Bank capital (the residual)
- Assets minus liabilities — the owners' stake and the buffer that absorbs losses before depositors are hit. It is net worth, not a vault of cash. Because the sliver is thin (often under 10% of assets), a small percentage loss on assets can wipe out a large share of capital.
- Net interest margin (NIM)
- Net interest income divided by total assets — the weighted interest-rate spread on lending, analogous to a gross margin. It measures only the interest side and ignores fee income, operating costs and tax.
- Return on assets (ROA)
- Net profit after tax divided by total assets. It captures both the interest margin and the fee margin net of all costs and tax, so it — not NIM — is the measure of total profitability. Bank ROAs are small, often around 1%.
- Leverage bridge (DuPont)
- ROE = ROA × (assets/capital). The equity multiplier scales a small asset-level return into a large owner-level return, and it is symmetric: it magnifies losses on equity exactly as hard as it magnifies gains.
- Efficiency ratio
- Operating (non-interest) expense divided by total revenue (NII + non-interest income) — the share of each revenue dollar eaten by costs. Lower is better; a well-run bank sits in the 40s–50s%.
Bank Financial Analysis FAQ
What is the difference between NIM and ROA?
NIM is the interest margin only — net interest income over total assets — so it measures just the lending spread. ROA is net profit after tax over total assets, which captures the interest margin AND fee income AND operating costs AND tax. They share a denominator but measure different things. The classic exam question 'which ratio captures fee income?' is answered by ROA, never NIM.
Why is a bank's ROE so much bigger than its ROA?
Pure leverage. ROE divides profit by the thin capital sliver, while ROA divides it by the large asset base, and the gap between them is the equity multiplier (assets/capital). A bank with ROA 1.6% and leverage 12× earns ROE of about 19.6%. But the multiplier is symmetric — if ROA turns negative, leverage magnifies the loss on equity just as hard, which is precisely why regulators impose capital requirements.
How do I get the denominators right under exam time?
ROE divides by capital, not assets; ROA divides by assets, not capital; the bridge multiplies ROA by assets/capital (not capital/assets, which would shrink it). A reliable sanity check: for a levered bank ROE should come out bigger than ROA. If it doesn't, you flipped a denominator. Always cross-check ROE from the bridge against ROE computed directly as NPAT/capital.
What is the exam's favourite bank-analysis question?
A stylised balance sheet plus a short income strip, where you build bank capital from the identity (assets minus liabilities), then run the whole ratio ladder: capital/assets, NIM, ROA, leverage, ROE (bridge then verify direct), efficiency ratio and NPL ratio. The same engine then narrates the 30% group report, so the calculation and the interpretation sentence are worth practising together.
Exam move
Drill the ratio ladder until you can run it from a blank balance sheet without thinking: capital as a residual → capital/assets → NIM → ROA → leverage → ROE (bridge, then verify direct) → efficiency & NPL. Lock the denominators — capital for ROE, assets for ROA, total revenue for the efficiency ratio — because that is where most marks are lost. Always tie ROE out two ways (bridge vs direct); agreement is your proof. Remember the direction rules: for the efficiency ratio lower is better, for the NPL ratio higher is worse. Finally, practise the one-sentence interpretation the report rewards (a healthy spread and ROA, but thin capital means high leverage that magnifies any loss), because the calculation and the narration are tested as a pair.
