Thursday, February 19, 2009

Some new vehicle travel numbers

As I sit waiting for “This Week in Petroleum” to update I wandered over to the Federal Highway Administration to see if the latest Traffic Volume data was available. And it is, with the numbers for December 2008 just having been posted. The reason for the interest can be seen in the plot of miles driven, that they provide, and this is the new one:

Source FHWA

It actually looks a little more fearsome than it is.
UPDATE: The TWIP information has been added.

The data plotted above is a 12-month rolling average, and when you look at the individual month data, and use the urban highways plot as representative (the argument also holds for the rural and total) you can see that driving started to drop last December relative to 2006. Through all of last year it has been down relative to 2007, but with the December figures we are starting to stabilize, and come closer to the previous years figures.

Source FHWA

In fact if you look at the regional plot, the Northeast is slightly up on last year, and most of the other regions are not down much (relative to the previous drops of around 5%).

Source FHWA

So this may mean that for most of us the situation may be stabilizing (sorry West Coast, not you yet). Now this data is still a couple of months old, and it shows that the drop is still going on, but demand for fuel may be leveling off.

Added: A little late today, the TWIP now is up, let me add the two plots from this week that I have been looking for. The first is the demand curve. Now we know from the second figure that driving started its dive last December, so the comparison is with what was already turning into a drop, but if you look at this week’s gasoline demand:

Then you can see that current demand, which equated to the same number as this time last year last week, has just risen above it this week based on four-week averaging. However if you look at the tabulated numbers the week saw a drop of 100,000 bd on average, which is down 200,000 bd on a year ago.


Which takes up back to see what is going into the refineries, and this is still paralleling the drop of last year. It is currently about 300,000 bd below last year’s figure.

Gas prices have now been rising for 3 weeks, while home heating oil prices have been falling for five weeks. But even as refinery input bottomed out at this time last year, so it appears to be doing the same again this year, although we may have to wait a week or two to see a clearer trend.



  1. Can you help me understand something in TWIP?

    TWIP reports refinery inputs as 14.2 mbd (4-week average), which isn't far off the level of a year ago. The highest they've been recently was 16.2 mbd, in July 2007, and the average for 2007 was 15.2 mbd.

    We're used to thinking that the US consumes a quarter of the world's oil, around 20 mbd. The BP workbook gives 20.7 mbd as the actual average consumption for 2007.

    TWIP's imports of gasoline plus distillates averaged 1.4 mbd in 2007. Adding these to the refinery inputs, we have an apparent shortfall of 4.2 mbd compared to the estimated consumption. What's included in this shortfall?

  2. There are other inputs to the refinery, other than just crude oil. If you go to the refinery and blender net input page and you divide the numbers by the days in the month and take June 08, for example. The total input to the refinery of all fluids was 17.84 mbd. Of this only 15.38 mbd was crude oil - the rest was made up as you see from the table. In addition some crude may be put into the SPR. We imported 1.3 mbd of gasoline in June, and about 0.2 mbd of distillates. That gets us to 19.3 mbd, I am not sure if corn ethanol is counted in the total refinery package or not, will check.