Futures Contract Value Depends on Quoted Price Units
Summary
The document explains why multiplying a futures contract size by its displayed price can produce a mistaken contract value. The key is the price unit: a soybean future may be quoted in cents per bushel rather than dollars per bushel. Contract size must be multiplied by a price interpreted in the exchange’s specified units, with the resulting amount converted consistently into currency.
The broader lesson is that market data and trade systems need explicit price semantics. Exchanges define acceptable quoting conventions, and a single contract may permit more than one convention. Systems often rely on feed-specific assumptions instead of carrying unit metadata, which can cause errors if conventions differ or change. The example illustrates the issue, but the document does not provide a general conversion procedure for every futures contract; users must verify the particular contract specification and data source.
Key ideas
- A futures price must be interpreted with its unit before calculating contract value.
- Contract size multiplied by a cents-per-unit quote requires conversion from cents to dollars.
- A contract can allow multiple valid price conventions.
- Trading systems should preserve or reliably document the quote convention used by each data source.
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Full text
# Future Contract Value # Future Contract Value Soybean future on Bloomberg's security description, I see Contract size = 5,000 bushels price = 1,200 usd/bushel contract value = $60,000 How is the contract value of $60,000 derived? Isn't the contract: value = contract size * price which in this case = 5,000 bushels * price of 1 bushel of 1,200 = $6,000,000 ? ## Answer by ThatDataGuy (score 2) https://quant.stackexchange.com/a/78268 This is a great example of how the implicit semantics of prices can catch folks out. In trading, and especially when creating trading software, it's very important to understand exactly what the specific price semantics are for given deal and data input. You should not assume that the literal, quoted price for securities is always an amount of a currency. Moreover, you should never assume that two prices for the same thing always have the same semantics. For example, futures contracts have set definitions of what a price is and how it is written that are specified by the exchange. However, some futures contracts have multiple allowed price semantics. Eg, USD / bushel and c / bushel may both be perfectly valid, and it's up to the reader to know which is which. This is usually fine for humans who have knowledge of the market, but for computers it's not usually obvious / possible to disambiguate. As such, most systems have to either propagate the additional information, or establish some convention like "Soybean futures prices coming on this feed / interface are always quoted in c / bushel". Most systems do the latter as it's more performant, but can lead to bugs when the incoming data changes relative to the convention.
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