In the broadest sense, commodities are undifferentiated products or services. Producers are price takers–that is, they are forced to accept whatever price the market offers.
Commodity products are often marked by boom and bust cycles, that is, periods where supply exceeds demand, in which case prices can plummet, followed by ones where supplies fall short and prices soar.
For agricultural commodities, the cycle can be very short. For crops, the move from boom to bust and back may be as little at one planting season, or three-six months. For farm animals, like pigs, chickens or cows, it may be two years.
For minerals, which right now is probably the most important commodity category for stock market investors, cycles can be much longer. Base and precious metals have recently entered a period of overcapacity. The previous one lasted around 15 years. One might argue that prices for many metals have already bottomed. I’m not sure. But I think it’s highly unlikely that they will rise significantly for an extended period of time.
Oil is a special case among mined commodities. Lots of reasons
–the market is huge, dwarfing all the metals other than iron/steel.
–there’s a significant mismatch between countries where oil is produced and where it’s consumed.
–there’s one gigantic user, the US.
–for many years, there was an effective cartel, OPEC, that regulated prices.
To my mind, the most important characteristic of oil for investors at present is the wide disparity in out-of-pocket production costs between Saudi crude ($2 a barrel) on the one hand, and Canadian tar sands ($70? a barrel) on the other. US fracked oil ($40? a barrel) is somewhere in the middle. The lower-cost producers have gigantic capacity, and the potential to ramp output up if they choose. This wide variation in costs makes it very difficult to figure out at what price enough capacity is forced off the market that the price will stabilize. For example, Goldman, which has an extensive commodities expertise, has argued that under certain conditions crude might have to fall to $20 a barrel before it bottoms.
The oil and metals situation is important for any assessment of 2016, because:
–about 25% of the earnings of the S&P come from commerce with emerging markets, many of which depend heavily on exports of metals and/or oil for their GDP growth
–the earnings for about 10% of the S&P 500–the Energy, Materials and Industrials sectors–are positively correlated withe the price of metals and oil.
–a low oil price is a significant economic stimulus for most developed countries, meaning margins expand for companies that use oil as an input and consumers spending less on oil will have more money left to spend elsewhere.
As a result, one of the biggest variables in figuring out earnings fo the S&P next year will be one’s assumptions about mining commodities prices, especially oil.