Why Are Commodity Prices Falling?

CAMBRIDGE – Oil prices have plummeted 40% since June – good news for oil-importing countries, but bad news for Russia, Venezuela, Nigeria, and other oil exporters. Some attribute the price drop to the US shale-energy boom. Others cite OPEC’s failure to agree on supply restrictions.

But that is not the whole story. The price of iron ore is down, too. So are gold, silver, and platinum prices. And the same is true of sugar, cotton, and soybean prices. In fact, most dollar commodity prices have fallen since the first half of the year. Though a host of sector-specific factors affect the price of each commodity, the fact that the downswing is so broad – as is often the case with big price swings – suggests that macroeconomic factors are at work.

So, what macroeconomic factors could be driving down commodity prices? Perhaps it is deflation. But, though inflation is very low, and even negative in a few countries, something more must be going on, because commodity prices are falling relative to the overall price level. In other words, real commodity prices are falling.

The most common explanation is the global economic slowdown, which has diminished demand for energy, minerals, and agricultural products. Indeed, growth has slowed and GDP forecasts have been revised downward since mid-year in most countries.