EPDM: Correlation
Prices it moves with, and why
EPDM is made from ethylene, propylene and a small amount of a diene, and resists heat, ozone and weather. It is used in car seals and hoses, roofing membranes and cable insulation, so vehicle and construction demand drive it.
Proxy US PPI: synthetic rubber incl. SBR and ethylene-propylene index (BLS base period) · monthly, Jan 2006 to Sep 2026There is no free public price for EPDM 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 linkEPDM and Ethylene
Monthly changes 0.36 weak correlation 12-month changes 0.66 moderate correlation Last 5 years 0.56 monthly changes Lead or lag +1 mo Ethylene tends to lead by 1 month (r 0.48) Price function, Jan 2006 to Sep 2026 EPDM ≈ 43.7 × (Ethylene)0.27 R² 0.21 On this fit, a 10% higher ethylene price goes with a 2.6% higher EPDM price over the long run. Units: index (BLS base period) and index (BLS base period). The fit is loose, so treat the function as a rough guide.Chart: EPDM and Ethylene 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: EPDM price against Ethylene 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.Ethylene is the largest monomer in most EPDM grades. The petrochemical proxy moves with the synthetic rubber proxy at 0.36 monthly and 0.66 yearly, and 0.56 over the last five years.
weak co-movement month to month · 249 months Show chartsPropylene is the second monomer, and its share sets the rubber's flexibility. It shares the petrochemical proxy with ethylene, so the measured figures are the same and cannot separate the two.
weak co-movement month to month · 249 months Show chartsEthane from gas feeds the US crackers that supply much of the ethylene for EPDM. European gas moves with the rubber proxy at 0.23 monthly and 0.66 yearly. The tie is loose monthly.
weak co-movement month to month · 249 months Show chartsDoor seals, window channels and hoses in cars are the largest EPDM use. The vehicle price proxy does not move with the rubber proxy, 0.03 monthly, because car prices follow model cycles.
little or none co-movement month to month · 249 months Show chartsEPDM insulates medium-voltage and flexible power cables, so grid and wind farm build-out adds demand. The cable price index moves with the rubber proxy at only 0.05 monthly and 0.47 yearly, as cable prices are driven mostly by copper.
little or none co-movement month to month · 249 months Show chartsHow 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.