Contango, backwardation, and roll yield
| Curve shape | What it means | Effect on commodity ETF |
|---|---|---|
| Contango | Futures price > spot (typical for storable commodities like oil/grain/copper) | ETF loses roll yield each cycle -- can erode 5-15% annually in steep contango |
| Backwardation | Futures price < spot (typical for short-supply commodities and seasonal-demand commodities) | ETF gains positive roll yield -- enhances returns above the spot-price move |
| Flat curve | Futures price ~ spot across maturities | Roll yield is roughly zero -- ETF return tracks spot move minus fees |
The 2020 crude oil collapse and USO
Commodity exposure without the futures roll
For investors wanting commodity exposure WITHOUT the futures-roll problem, the alternatives are: (1) physical-holding ETFs for precious metals (GLD, SLV -- gold/silver have low storage cost relative to value), (2) commodity-producer equities (energy E&P, mining stocks), (3) structured products that smooth across multiple futures maturities (DBC uses an optimized roll strategy). Each has tradeoffs: producer equities add operating leverage and management risk; physical-metal ETFs have storage fees (typically 25-50 bps); optimized-roll ETFs reduce but don't eliminate contango drag.
Compare a commodity ETF to its spot price
Why commodity ETFs disappoint as inflation hedges
Commodity-futures ETFs are usually a POOR long-term inflation hedge despite the marketing. The contango drag erodes returns over multi-year holding periods even when commodity prices rise. The empirical evidence is genuinely contested: Erb and Harvey (2006) document the contango/roll-yield drag that has left commodity-futures INDICES well behind equity inflation hedges since 2000, while Gorton and Rouwenhorst (2006) — the canonical pro-commodities paper — found collateralized futures earned equity-like returns over 1959-2004. The post-2004 out-of-sample record has favored the skeptics. If you want inflation protection, TIPS (Treasury Inflation-Protected Securities) and equities of pricing-power companies have outperformed commodity futures over the past 20 years. Commodity exposure is a tactical play, not a strategic allocation, for most investors.
Negative carry, contango drag, and tactical use
Commodities have negative carry baked into the structure. Contango drags commodity-futures ETF returns; backwardation enhances them. The 2020 USO collapse is the case study for misunderstanding this. For long-term portfolio inflation hedging, TIPS and pricing-power equities have empirically beaten commodity futures. Use commodity ETFs tactically, not strategically.
The tax wrapper: K-1s and Section 1256 contracts
The tax wrapper matters as much as the roll yield. Many commodity ETPs (USO, DBA and peers) are structured as limited partnerships: they issue a Schedule K-1 (extra filing complexity, sometimes state filings) and their futures are Section 1256 contracts -- marked to market every year and taxed 60% long-term / 40% short-term regardless of holding period, which can create taxable income in years you never sold. Commodity ETNs avoid the K-1 but substitute the issuing bank's credit risk. Check the wrapper (fund prospectus, 'Tax Information') before buying.
Sit with the ideas.
A commodity ETF tracking crude oil futures returned -8% over a year where the spot price of crude was actually flat. What is the most likely explanation?