Contango

Contango is the normal state for most commodity futures markets because futures prices incorporate the cost of carrying the underlying asset — storage costs, insurance, and financing — over the contract's life. In a standard contango market, a trader who buys a near-term futures contract and rolls it forward to the next expiration repeatedly will suffer a negative roll yield, because they are constantly selling the cheaper near-dated contract and buying the more expensive deferred contract.

For oil markets, the most commonly cited example of contango involves crude oil storage. When global oil supply is plentiful and storage facilities are near capacity, the market goes into steep contango as holders of physical oil pay substantial storage costs to defer delivery. This was dramatically illustrated in April 2020 when WTI crude oil futures briefly traded at negative prices — a historic event reflecting extreme contango and storage capacity constraints.

For equity index futures, contango arises from the cost-of-carry formula. The theoretical fair value of an S&P 500 futures contract equals the spot index value multiplied by one plus the risk-free rate minus the dividend yield, over the time to expiration. Because the short-term risk-free rate is typically positive and most S&P 500 stocks pay dividends, the futures price in a normal environment trades slightly above the spot index for shorter maturities, though this relationship can invert when dividend yields are high relative to rates.

VIX futures are one of the most notable contango-dominated markets. Because realized volatility tends to be lower than the implied volatility priced into futures, VIX futures consistently trade above current VIX spot levels in normal environments. This persistent contango structure generates a strong negative roll for long VIX ETF products, which mechanically buy near-dated VIX futures and roll them into more expensive deferred contracts each month.

Understanding contango is essential for anyone trading commodity ETFs that use futures to track spot prices, as the roll cost embedded in contango markets creates structural return drag that can significantly disconnect ETF performance from the actual commodity price over time.