Direct answer
To assess Carry Relationship, collect data that lets you (1) define the interest-rate “carry” mechanism you’re evaluating, (2) specify inputs and how you obtained them, (3) ensure timeliness, and (4) run basic consistency and quality checks. Because carry depends on market conditions and implementation details, you also need data about costs and the assumptions behind any calculation. The goal is not prediction, but an internally consistent explanation you can verify.
Mechanism or definition (what you are assessing)
Carry Relationship is commonly described as the economic tendency for returns to be influenced by an interest-rate differential between two currencies, when one currency position earns interest and the other incurs it. To assess it, you typically need:
- Interest-rate inputs (the “carry” engine)
- The specific rates you use (for example, a short-term benchmark or an instrument-linked reference).
- The currency mapping: which rate belongs to the base currency and which to the quote currency.
- The date convention: when the rates are observed and how they align with your evaluation period.
- Exchange-rate / valuation inputs for the currency move
- If you are assessing the realized outcome conceptually, you need enough data to understand valuation effects during the same horizon.
- Even if you don’t compute returns, you should record the exchange-rate data you would use to explain when interest-rate effects dominated versus when valuation changes dominated.
- Implementation assumptions and costs Carry is not only an interest-rate story; execution details can change results. Collect non-market assumptions and costs relevant to your scenario, such as:
- Spread or transaction cost assumptions.
- Financing assumptions consistent with your chosen carry definition.
- Any constraints or operational choices that affect effective carry.
Evidence or example (a checklist of inputs, provenance, and timeliness)
Use this control-checklist approach to structure your assessment inputs.
A. Inputs: what exactly must be on your worksheet
- Rate differential components: the two interest-rate values and their definitions.
- Time window: start/end dates and day-count or compounding convention if you compute an implied carry.
- Exchange-rate reference: the valuation measure (spot vs another reference) aligned to your window.
- Cost model: what costs you assume, and whether they are treated as fixed, proportional, or ignored.
- Assumptions list: what you assume about financing and how you align interest accrual with your horizon.
B. Provenance: where the data comes from
Record provenance for each input:
- Rate source and publication method (official statistics, central bank releases, or documented benchmarks).
- How exchange-rate values were obtained and whether they were adjusted or filtered.
- Whether your provider/platform documentation defines the rate conventions used.
C. Timeliness: how “fresh” the inputs are
You need to ensure alignment:
- Are rates from the same observation date range as your evaluation horizon?
- Are exchange-rate inputs contemporaneous with the rate data?
- If you use historical series, note that they reflect past regimes and may not generalize.
D. Quality checks: simple consistency tests
- Confirm that your rate definitions match between currencies (same benchmark family, same tenor, same interpretation).
- Validate units and scaling (percent vs decimal; annualized vs periodic).
- Check for missing values or irregular publication dates; document how gaps are handled.
Limitations and risks (material failure modes)
A careful assessment still has limitations.
- Assumption sensitivity: Carry Relationship depends on the exact interest-rate definitions and financing assumptions you use. If you change tenor, benchmark, or timing conventions, your computed “carry” may no longer match your explanation.
- Cost and execution risk: Real-world costs and how interest is effectively charged/credited can materially affect outcomes, especially over short horizons.
- Regime shifts: Historical relationships between interest differentials and realized currency valuation may weaken when market behavior changes.
- Tail events and volatility: Sharp moves in exchange rates can dominate interest effects, reducing the explanatory power of the carry component.
Verification or next question (how to independently verify)
To verify your understanding without relying on a prediction:
- Recreate your interest-rate differential from the documented source definitions and confirm the timing alignment.
- Check that any calculations state the full set of assumptions (rate definitions, window, units, cost treatment).
- Compare your explanation across at least two different historical windows to see whether the same mechanism story remains internally consistent.
- Identify which input is doing the work in your reasoning: interest-rate assumptions, exchange-rate valuation, or cost assumptions.