MTBE: Correlation
Prices it moves with, and why
MTBE is made from methanol and isobutylene and blended into petrol to raise octane, mainly in Asia and the Middle East since US states phased it out. Its price follows petrol and crude, with methanol cost and ethanol mandates also shaping demand.
Proxy US PPI: other basic organic chemicals index (BLS base period) · monthly, Jan 2006 to Sep 2026There is no free public price for MTBE 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 linkMTBE and Refining and reforming
Monthly changes 0.38 weak correlation 12-month changes 0.68 moderate correlation Last 5 years 0.47 monthly changes Lead or lag none No clear lead or lag Price function, Jan 2006 to Sep 2026 MTBE ≈ 43.0 × (Refining and reforming)0.30 R² 0.28 On this fit, a 10% higher refining and reforming price goes with a 2.9% higher MTBE price over the long run. Units: index (BLS base period) and index. The fit is loose, so treat the function as a rough guide.Chart: MTBE and Refining and reforming 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: MTBE price against Refining and reforming 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.Methanol supplies the methyl group of MTBE and much of its variable cost. Both share the same proxy index here, so no separate statistics are shown for this pair. Methanol price spikes squeeze MTBE margins when petrol does not rise as well.
Not enough overlapping price history to measure.MTBE is sold as a petrol component, so it is valued against other octane sources at the refinery gate. The refinery index moves with the basic organics proxy at 0.38 monthly and 0.68 yearly.
weak co-movement month to month · 249 months Show chartsPetrol prices follow crude, and MTBE prices follow petrol, often at a premium when octane is scarce. Brent moves with the proxy at 0.23 monthly and 0.58 yearly, diluted because the proxy covers many other chemicals.
weak co-movement month to month · 249 months Show chartsEthanol competes with MTBE as an octane blend, and ethanol mandates such as India's push MTBE out. The ethanol index moves with the proxy at 0.65 monthly and 0.78 yearly, but partly mechanically, as ethanol sits inside the proxy index.
moderate co-movement month to month · 249 months Show chartsIsobutylene comes from the same cracker C4 stream as butadiene and from refinery crackers, so cracker rates affect MTBE supply. The petrochemical proxy moves with the basic organics proxy at 0.29 monthly and 0.64 yearly.
weak 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.