In a seminal article, Samuelson (1965) proposes the maturity effect that volatility of futures prices should increase as futures contract approaches maturity. This study provides new evidence on the maturity effect by examining a more extensive set of futures contracts than previous studies and analyzing each contract separately. Using 6805 futures contracts drawn from 61 commodities, including some data from non-US markets, we find that the maturity effect is absent in the majority of contracts. In addition, the maturity effect tends to be stronger in agricultural and energy commodities than in financial futures. We also examine the hypothesis in Bessembinder, Coughenour, Seguin, and Smoller (1996), which states that negative covariance between the spot price and net carry cost causes the maturity effect in futures. Our results provide very weak evidence in favor of this hypothesis.
Daal, Elton and Farhat, Joseph, "Does futures exhibit maturity effect? New evidence from an extensive set of US and foreign futures contracts" (2004). Department of Economics and Finance Working Papers, 1991-2006. Paper 22.