Understanding this indicator
Copper connects this chart to industrial materials demand, including manufacturing, construction and electrical uses. Commodity prices connect physical supply and demand with financial markets. LME Copper is one window into that relationship. Production, inventories, transport and changing demand can all influence its price. A cycle view helps put short-lived price moves beside the slower changes that develop as the economy expands and slows.
The chart uses monthly price observations and compares each month with the same month a year earlier. Annual change is calculated using the logarithm of the price ratio. This puts different price levels on a comparable basis and makes the shift from strengthening to weakening annual performance easier to follow. It describes the quoted commodity price, not the return from rolling a futures position.
A year-on-year reading above zero means the price is higher than a year earlier; below zero means lower. A rising line can show that a decline is narrowing, rather than that the commodity has already gained over the year. Likewise, a falling line can show a shrinking annual gain. Keeping these comparisons separate from the latest daily price move helps make the cycle clearer.
Compare this commodity with the overall Commodity Cycle and, where useful, with Commodity Market Structure. A move shared by many commodities may reflect a broad change in economic conditions; a move confined to one product invites a closer look at its own supply and demand. Manufacturing activity and producer prices provide further context, without assuming that every commodity follows exactly the same timetable.
The green line isolates the 3–4-year Kitchin cycle from the historical data; it is a fitted cycle, not a forecast of the next turn. The lower chart shows the 7–10-year Juglar cycle and the 15–25-year Kuznets cycle. Comparing these time scales can reveal why a shorter upswing sometimes sits within a much longer period of weakness. The two main-chart axes use different scales, so compare their timing and direction rather than the height of one line against the other. Historical curves may change as the data are updated.