Commodities

Commodities are raw materials or primary agricultural products — crude oil, natural gas, gold, silver, wheat, corn and coffee among the most heavily traded examples — that are broadly interchangeable within a defined grade and traded on organized exchanges around the world. As a distinct asset class, commodities sit alongside stocks, bonds and real estate in a diversified investment portfolio, prized by many investors specifically for behaving quite differently from ordinary financial assets during inflationary periods.

Commodities trade both in physical, or "spot," markets and through derivative instruments such as futures and options contracts, which let producers, consumers and pure financial investors manage price risk or speculate on future price direction without ever having to physically handle the underlying raw material itself.

A bushel of wheat grown on one farm is treated as essentially identical to a bushel grown on another farm of the same grade, and this basic interchangeability is exactly what makes commodities tradeable on a standardized exchange in the first place: buyers do not need to personally inspect each individual seller's specific goods, only agree on the grade, quantity and delivery terms being traded.

Many ordinary investors gain commodity exposure not by buying literal barrels of oil or bars of gold directly, but through futures contracts, commodity-focused exchange-traded funds, or simply shares of companies whose underlying business is producing or processing those commodities.

Commodities are generally grouped into three broad categories: energy, covering crude oil and natural gas; metals, covering both industrial metals such as copper and precious metals such as gold and silver; and agriculture, covering grains, livestock, and so-called soft commodities such as cocoa, coffee and cotton. Precious metals like gold are frequently treated as a somewhat separate category, valued more as a store of value and inflation hedge than purely as an industrial input consumed in manufacturing.

Commodity prices tend to rise during periods of high inflation, since the rising cost of raw materials feeds directly through into broader economy-wide price levels, which is exactly what makes commodities a popular inflation hedge for portfolio managers. They also tend to exhibit relatively low correlation with traditional stocks and bonds, which can meaningfully improve a portfolio's overall diversification, though commodity prices are notoriously volatile, and unlike a stock or bond, a commodity itself pays no dividend or interest at all while simply being held in storage.

Major commodity exchanges, including the Chicago Mercantile Exchange and the London Metal Exchange, list standardized futures contracts that precisely specify the quantity, quality grade and delivery terms for each underlying commodity. The great majority of investors who gain commodity exposure through futures contracts never actually intend to take physical delivery of the underlying goods at all, instead closing out or systematically rolling their position forward to a later contract month before the original contract reaches maturity.

Retail investors who want commodity exposure without directly trading futures contracts themselves can typically access it through exchange-traded funds that either hold the physical commodity, as some gold funds do, or hold a rolling basket of futures contracts designed to track a broader commodity index, each approach carrying somewhat different cost, tax and tracking characteristics worth understanding before investing. A fund that must repeatedly roll expiring futures contracts forward into new ones can experience "roll yield" that causes its long-run return to diverge meaningfully from the simple spot price of the underlying commodity, a subtlety that often surprises investors who assume a commodity fund tracks the headline price they see quoted in the news.

Commodity prices are especially sensitive to sudden supply disruptions — a war affecting an oil-producing region, a drought damaging a grain harvest, or a mine closure limiting metal output — because, unlike a manufactured product, the physical supply of most commodities cannot be quickly expanded to meet a sudden jump in demand, which is why commodity price swings tend to be considerably sharper and faster than price movements typically seen in broad equity markets.