This paper studies the dynamic interaction between the net positions of traders and risk premiums in commodity futures markets. Short-term position changes are mainly driven by the liquidity demands of non-commercial traders, while long-term variation is primarily driven by the hedging demands...

"Commodity futures risk premiums vary across commodities and over time depending on the level of physical inventories, as predicted by the Theory of Storage. Using a comprehensive dataset on 31 commodity futures and physical inventories between 1969 and 2006, we show that the convenience yield...