Railway electrification and wireless power: Correlation
Prices it moves with, and why
Railway electrification costs come from overhead lines, substations and civil works, and depend on copper, steel and labour. Wireless power, from phone pads to road charging trials, depends on power electronics, copper coils and ferrite cores.
No public price Railway electrification and wireless power has no public monthly price series: Bought as custom infrastructure projects; no public price index.What its price moves with
Overhead contact wire is made of copper alloys because it must carry high current while resisting wear from pantographs. Copper prices feed into electrification costs, alongside the much larger costs of labour and civil works.
Not enough overlapping price history to measure.Steel masts, gantries and foundations hold up the overhead line, and the track itself is steel. Steel prices raise the cost of new electrified routes, though labour and access to the line usually matter more.
Not enough overlapping price history to measure.Traction substations convert grid power for trains, and wireless chargers need high-frequency inverters. Both depend on power semiconductors and transformers, whose costs and long delivery times shape project budgets and timetables for electrification schemes.
Not enough overlapping price history to measure.Electric locomotives and trains use the power that electrification provides. Cheaper traction equipment, and battery trains that recharge on short electrified sections, change how much line a railway needs to electrify.
Not enough overlapping price history to measure.Wireless charging for cars and buses is a growing use of inductive power. Its uptake depends on electric vehicle numbers and on whether drivers will pay more than for a plug for the convenience.
Not enough overlapping price history to measure.Wireless chargers use ferrite plates, made mainly from iron oxide with manganese or nickel, to guide the magnetic field. The material is cheap, but it is heavy and brittle, which shapes charger design.
No public price for iron oxide pigments, so the link is explained in words only.How to read these numbers
Correlation of monthly changes (the number in the coloured pill) compares how much each price moved, month by month, since 2006 or the first month both series exist. It runs from −1 to +1: near +1 the two usually rise and fall in the same months, near 0 there is no link, and a negative number means they tend to move in opposite directions. Above 0.7 is strong, 0.4 to 0.7 moderate, 0.2 to 0.4 weak.
12-month changes compare year-on-year moves, which shows whether two prices share the same cycles even when the month-to-month noise differs.
Price function is a straight-line fit of the two prices on logarithmic scales: price ≈ k × (partner price)β. β is how much this price moves, in per cent, for a 1% move in the partner over the whole period, and R² is the share of the variation the fit explains. Two prices that both drift up with inflation can fit well without any real link, so read it together with the monthly correlation.
Lead or lag checks whether the monthly correlation is clearly higher when one price is shifted by 1 to 6 months.
Correlation is not cause. The reasons on each card explain the economic link; the numbers show how strongly it has shown up in prices. Proxy series are US producer price indexes or related prices and can blur the real link.
Data: World Bank Commodity Price Data (Pink Sheet), October 2026; US Bureau of Labor Statistics producer price indexes, IMF primary commodity prices and US EIA prices via FRED, Federal Reserve Bank of St. Louis, retrieved November 2026. Calculations by this site.