Direct answer: what a worked example means for interbank market
A worked example is a step-by-step scenario that applies the basic interbank market mechanics to a small set of hypothetical numbers. It is not a forecast and it does not require live interbank quotes. The goal is to make the mechanics explainable and to show where costs and uncertainties enter.
In plain terms, the interbank market is a wholesale foreign-exchange market where large participants trade currencies with each other through common market processes (matching, quoting, settlement, and risk management). A worked example focuses on how an exchange rate quote (often expressed as bid and ask) translates into cashflows.
Mechanism or definition: how the numbers connect
A simple way to model interbank market quoting is to assume:
- A quoted bid price is what you would receive when selling the base currency.
- A quoted ask price is what you would pay when buying the base currency.
- The difference between ask and bid is the spread, which represents a cost and/or liquidity compensation.
- Settlement and timing can cause discrepancies between trade economics and the final cashflows.
A worked example therefore needs inputs that link a quote to a transaction:
- Trade size (how much currency is exchanged)
- Bid/ask prices (not “true” market value, just scenario inputs)
- Direction of trade (buy or sell the base currency)
- Any assumed fees (if included)
- An assumed settlement timeline (to highlight timing risk)
Worked numerical example (with explicit assumptions)
Below is one scenario that illustrates how interbank quoting mechanics can affect cashflows.
Assumptions
- Hypothetical quote: bid = 1.2500 and ask = 1.2502.
- Currency pair convention: the base currency is the first currency in the pair, and the quoted number is units of quote currency per 1 unit of base currency.
- Trade: you “buy” the base currency with quote currency (so you would pay the ask).
- Trade size: 10,000 units of base currency.
- Ignore commission and other provider costs (set to zero) to isolate spread effects.
- Settlement: you assume both sides settle consistently at the economics implied by the quote, but note in the limitations that real settlement and timing can differ.
Steps
- Determine the effective conversion rate for a buy using the ask: 1.2502 quote-currency per 1 base.
- Compute cash paid in quote currency:
- Quote paid = 10,000 × 1.2502 = 12,502 quote-currency units.
- Compute the “spread impact” versus if you could trade at the bid (a counterfactual):
- Counterfactual quote at bid would be 10,000 × 1.2500 = 12,500.
- Spread cost in this scenario = 12,502 − 12,500 = 2 quote-currency units.
What this example teaches
- Even with the same trade size, using ask versus bid changes the cashflow.
- The spread can matter materially when the spread is not negligible relative to the trade size.
- The example remains hypothetical because the bid/ask values are assumptions, not live data.
Limitations and risks (material failure modes)
- Bid/ask assumption may not hold at execution time. Real quotes can change between the moment you observe them and the moment the trade actually executes.
- Spread is not the only cost. In practice, there can be commissions, dealing costs, and other operational frictions; this example set them to zero to isolate one effect.
- Timing and settlement uncertainty. If settlement timing differs from the economic assumptions, cashflows can diverge from the simplified model.
- Liquidity can break the model. During low liquidity, quotes may widen or execution may become incomplete, so the bid/ask-based cashflow logic becomes less reliable.
Verification and next questions you can ask
To independently verify the relevant facts, focus on stable definitions and observable documentation:
- Confirm what “interbank market” means in the context you are researching (who participates, and what “wholesale” implies).
- Check how bid/ask is defined for the market you study (quote convention and trade direction).
- For your own scenario, verify your assumptions: trade size units, quote convention, whether any explicit fees exist, and what settlement timing is assumed.
If you want to go further, a useful next question is: what are the common limitations of interbank market and where do simplified bid/ask examples usually fail?