Unsaturated polyester resins: Correlation
Prices it moves with, and why
Unsaturated polyester resins are made by reacting glycols with maleic and phthalic anhydride, then diluting with styrene. Prices follow these oil-derived inputs and demand for boats, pipes, tanks and construction composites, mostly on negotiated contract terms.
Proxy US PPI: thermosetting resins and plastics materials index (BLS base period) · monthly, Jan 2006 to Sep 2026There is no free public price for unsaturated polyester resins itself, so this tab uses the closest public series as a stand-in. Read the numbers as an indication, not as the price of this exact item.
What its price moves with
Selected linkUnsaturated polyester resins and Styrene
Monthly changes 0.22 weak correlation 12-month changes 0.74 strong correlation Last 5 years 0.15 monthly changes Lead or lag none No clear lead or lag Price function, Jan 2006 to Sep 2026 Unsaturated polyester resins ≈ 15.5 × (Styrene)0.52 R² 0.90 On this fit, a 10% higher styrene price goes with a 5.1% higher unsaturated polyester resins price over the long run. Units: index (BLS base period) and index (BLS base period).Chart: Unsaturated polyester resins and Styrene prices rebased to 100 at Jan 2006, log scale
Both prices rebased to 100 at Jan 2006, on a log scale so equal percentage moves look the same size.Chart: Unsaturated polyester resins price against Styrene price, monthly, log scales, with fitted line
Each dot is one month; paler dots are older (2006), darker dots recent (2026); the ringed dot is the latest month. The dashed line is the fitted price function. Both axes are logarithmic.Styrene makes up a large part of finished resin and cross-links it during curing, so its cost passes straight through. Against the cyclic intermediates proxy, monthly moves correlate at 0.22 but yearly moves at 0.74, showing pass-through that builds over several months.
weak co-movement month to month · 249 months Show chartsPropylene glycol, made from propylene oxide, is the usual glycol in these resins. The basic organic chemicals proxy correlates with the resin index at 0.24 for monthly moves, 0.74 for yearly moves and 0.29 over the last five years, consistent with shared petrochemical costs.
weak co-movement month to month · 249 months Show chartsEvery ingredient of these resins traces back to oil or gas liquids, but several conversion steps and contract pricing dampen the link. Monthly moves correlate at just 0.05, rising to 0.50 for yearly moves, and oil tends to lead by about 2 months.
little or none co-movement month to month · 249 months Show chartsWind turbine nacelle covers, some blades and many other composite parts use polyester or epoxy resins with glass fibre. The wind proxy is a general US turbine and generator price index, not a composites series, so monthly moves correlate at only 0.09.
little or none co-movement month to month · 184 months Show chartsThese resins are nearly always used with glass fibre, which is made from silica sand, and the two are bought together for laminates. They share construction and marine demand, but sand has no public series here, so the link is shown as text only.
Not enough overlapping price history to measure.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.