COMMODITY SUPERCYCLES · 1850–2025
The prices of oil, copper, wheat and the rest do not just rise and fall with the business cycle every few years. They also ride much bigger waves of about 30 years: 15 or so years of rising prices, then 15 or so years of falling ones. These are called supercycles. This site uses 175 years of data on 42 commodities to check whether the waves are real, why they happen, and where we are now.
In three lines
Compare each year’s price with its normal level (the average price you would expect in the long run). For decades at a time prices sit above that level, then for decades below it. That long swing is the supercycle.
Technically: the 20–70-year component of the real price index around its long-run trend. Shorter ups and downs, such as ordinary booms and recessions, are removed. How it is calculated is on the Were they real? page.
Each wave rose for about 15 years. What set it off was different each time, but it was always a big jump in demand.
1903 → peak 1917 → 1932
1932 → peak 1947 → 1966
1966 → peak 1981 → 1996
1996 → peak 2011 → now
If price moves were random, at any time about half the commodities would happen to be above their normal level, and the share would stay inside the grey band. Instead, nearly all 42 were expensive at the same time, then nearly all were cheap at the same time, again and again.
The waves also survive a different way of removing inflation, and their dates match those found by economists who studied the question independently.
When a large economy industrialises and urbanises, its use of steel, copper and energy rises for a decade or more, longer than a normal business cycle.
Mines take more than 16 years on average from discovery to first output (IEA, major mines that started in 2010–19). Higher prices cannot bring new supply quickly.
Projects approved at high prices start producing just as demand growth slows, and the surplus drives a long downswing.
One surprise in the data: farm goods, which can be replanted every year, ride the same waves about as strongly as mined goods. So it is not only about slow mines; something lifts all commodities together, such as world growth and inflation.
The fourth wave peaked in 2011. Since 2020 prices have risen, some a lot, but the 30-year wave line is still near the bottom (-3% in 2025). The two do not contradict each other: the wave line only turns up once a rise has lasted for years, and from the data so far a lasting rise and a short one look the same, and this year’s jump is not in the annual data yet. The same situation has come up three times before; twice it became a big wave.
Historically expensive
In between
Historically cheap
Number: how high today’s price is in its own history since 1960 (0 = cheapest month, 100 = dearest). Prices after inflation, Aug 2026.
Compared with the same stage of the 2000s wave, prices overall have risen less (×1.17 against ×1.55), but about as many commodities have risen by 20% or more (13 against 11 of 26). The leaders differ: oil then, gold and silver now. Whether this is a new big wave will only be clear years from now.
Updated 29 Sep 2026 02:33 JST · annual data to 2025 · monthly prices to Aug 2026