On the other side of this trade would be the speculator who
buys winter contracts and shorts non-winter contracts
providing liquidity to the natural hedgers. In exchange for
taking on this risk, the speculator should receive compensation
on average. This might explain the positive average return to
this strategy over time. Thus, the excess returns from a long
winter, short non-winter trade in September might be a
compensation to speculators for supplying liquidity to natural
hedgers, which consist of storage operators and natural gas
producers