It’s time for our monthly look at how the long-only commodity ETFs are performing versus simply holding the December futures contract and rolling annually. And, since we’re now in December 2012, our futures positions have “rolled” over to begin reflecting December 2013 futures contracts.

Crude oil climbed a few points higher this month, though it remained in the red for the year. Natural gas, on the other hand, fell around 5% from October in both the futures contract and ETF. Corn remained basically flat, falling just -0.2% from last month in futures and -0.7% in the ETF. In terms of the underperformance between the ETFs that we track and the December futures contract, underperformance widened slightly for all three commodities.

Futures trading is complicated, presents a risk of loss, and isn’t for everyone – especially since past market performance doesn’t necessarily indicate future results – but given the numbers, we’re left scratching our heads. Ultimately, we prefer a commodities investment strategy that can benefit from both rising and falling prices (like managed futures). But if you’re going to adopt a long-only strategy… we’ve yet to receive a good answer to the question: why invest in an ETF when you can just roll December futures contracts annually?

Read ‘em and weep:

Disclaimer: past performance is not necessarily indicative of future results.