10.1 Commodities and Commodity Derivatives: Sectors, Participants, Futures Returns & Indexes
Key Takeaways
- Total return on a fully collateralized commodity futures position is the sum of price return, roll return, and collateral return, and roll return is positive in backwardation and negative in contango.
- The theory of storage explains the futures basis through the cost of carry less the convenience yield, so a high convenience yield from tight inventories produces backwardation.
- The insurance (hedging pressure) theory holds that producers pay a premium to hedge, so futures trade below expected spot prices and long speculators earn a risk premium.
- Commodity index construction choices such as weighting by production, liquidity, or fixed weights, and the roll schedule, drive most of the return dispersion among commodity indexes.
- Commodities are valued by the discounted expected future spot price rather than by discounting cash flows, because a physical commodity generates no income stream.
10.1 Commodities and Commodity Derivatives: Sectors, Participants, Futures Returns & Indexes
Blueprint note: Introduction to Commodities and Commodity Derivatives is one of the four Alternative Investments learning modules at Level II, alongside two real estate modules and hedge fund strategies. Vignettes present a commodity portfolio with a futures curve exhibit and ask for a return decomposition or an interpretation of the curve shape.
1. Commodity Sectors and Their Life Cycles
| Sector | Examples | Distinguishing characteristics |
|---|---|---|
| Energy | Crude oil, refined products, natural gas | Largest sector by index weight; storable but costly; strong seasonality in natural gas; geopolitically sensitive supply |
| Base metals | Copper, aluminium, zinc, nickel | Cheap to store and non-perishable; demand tracks the industrial cycle closely; long lead times to add supply |
| Precious metals | Gold, silver, platinum | Very low storage cost relative to value; gold behaves partly as a monetary asset rather than an industrial input |
| Livestock | Cattle, hogs | Perishable; storage is effectively impossible, so the cost-of-carry link between spot and futures is weak |
| Grains | Corn, wheat, soybeans | Annual harvest cycle creates pronounced seasonality; storable between harvests with meaningful cost |
| Softs | Coffee, sugar, cotton, cocoa | Concentrated geographically, so weather in one region drives global prices |
Life cycle — the path from production through trading or consumption — differs in ways that matter for the futures curve:
- Grains have a single harvest and then a drawdown, so the curve typically shows a step at each new crop year and inventories are highest immediately after harvest.
- Natural gas is produced continuously but consumed seasonally, so storage cycles produce a repeating seasonal curve shape with injection and withdrawal seasons.
- Livestock cannot be stored, so the futures curve reflects expected production timing rather than carry.
- Metals have continuous production and consumption with large above-ground inventories, so their curves are the closest to a clean cost-of-carry relationship.
Valuation contrast. Equities and bonds are valued by discounting the cash flows they generate. A physical commodity generates no cash flow and in fact costs money to hold, so it is valued as the discounted expected future spot price, with the futures price serving as the market's observable estimate.
2. Participants in Commodity Futures Markets
| Participant | Motivation | Typical position |
|---|---|---|
| Hedgers (producers) | Lock in a selling price for future output | Short futures |
| Hedgers (consumers) | Lock in an input cost | Long futures |
| Informed investors and speculators | Take directional or relative-value risk for return | Either side; provide liquidity to hedgers |
| Liquidity providers / market makers | Earn the bid–ask spread and short-term imbalances | Flat over time, intraday either side |
| Arbitrageurs | Exploit deviations between spot, futures, and storage costs | Offsetting cash-and-carry positions |
| Analysts and exchanges | Do not take positions; set rules, margins, and disseminate information | None |
The balance between producer and consumer hedging is what the hedging pressure hypothesis rests on: when producers hedge more than consumers, the net short hedging position must be absorbed by long speculators, who require compensation.
3. Contango, Backwardation, and the Three Theories
The shape of the curve
- Backwardation: futures price below the current spot price; the curve slopes downward. A long futures position rolling forward buys the next contract at a lower price than the one it sells, generating a positive roll return.
- Contango: futures price above the current spot price; the curve slopes upward. Rolling forward generates a negative roll return.
Theory 1 — Insurance (hedging pressure)
Keynes's normal backwardation argument: producers are net hedgers and pay a premium to transfer price risk. Consequently the futures price sits below the expected future spot price, and long speculators earn that discount as a risk premium as the futures price converges to spot. The prediction is that markets are normally backwardated. The empirical objection is that consumers also hedge, and in several markets they hedge more, which produces contango.
Theory 2 — Theory of storage
The futures price is determined by the cost of carry net of the convenience yield:
The convenience yield is the non-monetary benefit of holding the physical commodity — the option to keep a plant running through a supply interruption. It rises when inventories are low and falls to near zero when inventories are ample.
- Low inventories → high convenience yield → backwardation.
- High inventories → low convenience yield → contango.
This theory explains why the same commodity moves between the two states as the inventory cycle turns, which the insurance theory cannot.
Theory 3 — Hedging pressure hypothesis
A generalisation of the insurance theory: the curve's shape depends on the net balance of producer and consumer hedging demand. When producers dominate, backwardation; when consumers dominate, contango. It accommodates the observed regime switching that pure normal backwardation does not.
4. Decomposing the Total Return
For a fully collateralized long futures position:
| Component | Definition | Driver |
|---|---|---|
| Price return | Change in the price of the front futures contract over the period | Spot price movement |
| Roll return | Gain or loss from closing the expiring contract and opening the next | The shape of the curve: positive in backwardation, negative in contango |
| Collateral return | Return on the cash posted to collateralize the notional | The risk-free rate, since a fully collateralized position holds the full notional in bills |
Worked example. An investor holds a fully collateralized long position in a commodity. Over the year:
- The front contract price rises from 82.00 to 88.00.
- At each quarterly roll the near contract trades at 88.00 and the next contract at 89.76, so the position is rolled at a 2.0% loss each time, on 100% of the position, four times a year.
- Treasury bills yield 4.3%.
Computing:
- Price return: $(88.00 - 82.00)/82.00 = \textbf{+7.32%}$
- Roll return: $-2.0% \times 4 = \textbf{-8.00%}$
- Collateral return: $\textbf{+4.30%}$
- Total return: $7.32% - 8.00% + 4.30% = +3.62%$
The commodity's price rose 7.32%, but the investor earned only 3.62%, because a persistently contangoed curve consumed most of the gain. This wedge between spot price performance and investable index performance is the most-tested idea in the module, and it explains why long-only commodity index returns have repeatedly lagged headline spot prices.
Under backwardation the arithmetic reverses: a flat spot price with a curve rolling at +1.5% per quarter produces a positive total return of about 6% plus the collateral yield, from curve shape alone.
5. Commodity Swaps
A commodity swap exchanges a series of payments based on a commodity price. The main structures:
| Structure | Mechanics | User |
|---|---|---|
| Excess return swap | One leg pays the commodity's excess return (price plus roll), the other a fixed rate | An investor seeking exposure without managing the futures roll |
| Total return swap | As above, plus the collateral return | An investor replicating a fully collateralized index position |
| Basis swap | Exchanges the price differential between two grades, locations, or delivery months | A refiner hedging a crude quality or location differential |
| Variance / volatility swap | Settles on realised variance or volatility rather than price | A hedger of price uncertainty rather than price level |
Swaps let an institution obtain index exposure without operational responsibility for rolling contracts and posting margin, at the cost of counterparty credit exposure to the dealer.
6. Commodity Index Construction and Why It Matters
Index construction choices produce large differences in realised returns even when the underlying commodities are identical.
| Choice | Options | Effect |
|---|---|---|
| Constituent selection | Broad versus energy-heavy | The single largest driver of return dispersion, because energy dominates aggregate commodity volatility |
| Weighting scheme | World production, liquidity, fixed equal weights | Production weighting concentrates in energy; equal weighting tilts toward agriculture and metals |
| Rolling methodology | Front-month roll; deferred-month roll; dynamic roll that selects the contract minimising contango | Determines how much of the negative roll return in a contangoed market the index actually incurs |
| Rebalancing frequency | Monthly, quarterly, annual | Frequent rebalancing generates a rebalancing return by systematically selling appreciated and buying depreciated constituents |
Two consequences the exam draws out:
- An index tracking a commodity is not the commodity. An investor cannot capture the spot price return without incurring the roll, so index returns and spot price changes diverge, sometimes by a great deal, over multi-year horizons.
- Diversification within the index and the rebalancing effect mean a commodity index can produce a positive return even when the average constituent's price return is close to zero, because volatile, imperfectly correlated constituents that are periodically rebalanced generate a rebalancing premium.
Level II traps in the commodities module
- Assuming backwardation means a falling price. It describes the shape of the curve, not the direction of the spot price.
- Forgetting the collateral return in a total-return decomposition.
- Reading a positive price return as a positive total return in a contangoed market.
- Attaching the convenience yield to high inventories; it is high when inventories are low.
- Valuing a commodity by discounting cash flows; a physical commodity has none, so it is valued as the discounted expected future spot price.
An investor holds a fully collateralized long position in a commodity futures contract. Over the year the front contract price rises from 82.00 to 88.00, the position is rolled quarterly at a 2.0% loss each time, and Treasury bills yield 4.3%. What is the approximate total return, and what does it demonstrate?
Inventories of a storable industrial metal fall sharply following a mine disruption. Under the theory of storage, what happens to the shape of the futures curve, and why?
Two broad commodity indexes hold similar constituents but report materially different multi-year returns. Which construction difference is most likely to explain the gap?