US vehicle-miles in December down less than previous months - news less bad

December estimates by FHWA of traffic  throughout the US in December 2008 (2008-12) show a decline of 1.6% in vmt on 2007-12, the smallest drop in the previous corresponding period (pcp) in eight months. Urban interstate traffic was level on pcp, while rural interstate traffic was 1.6% lower.

A sharp regional difference shows. The west is where the traffic decline seems most serious in the December numbers - a December on December (Dec/Dec) decline there of 4.8%. Outside the west the Dec/Dec is quite mild - around one percent, except in the northeast where its just a tad (0.5%) ahead of the same month last year.

Data is from a monthly FHWA publication "Traffic Volume Trends" and is based on some 4,000 traffic counts around the country.

That could be good news. But it might not be. The Dec/Dec figures could well be as much a measure of the decline in Dec 2007 as any moderation of the declining trend in Dec 2008.

Moving average showed smaller decline in Dec

The 12 month moving average - the last 12 months data aggregated - showed a small decline Nov 2008 (2926b) to Dec 2008 (2922b), a drop of just 4b. In previous months the moving average had declined 13b Nov, 10b Oct, 11b Sep, 15b Aug, 10b Jul, 14b Jun, 10b May, 4b Apr, 11b Mar, 2b Feb, 2b Jan,  4b Dec 2007.

November 2007 was the peak of traffic at 3038b. The decline over 13 months is 116b veh-miles or 3.8%. You have to go back to Mar-Apr 2004 to get vmt as low as Dec 2008's 2922b. In effect 3.5 years growth in traffic has been lost in the last year.

For the year as a  whole US road travel was down 3.6%, 2008 seeing an estimated 2922b vmt vs 2007's 3030b. That's a decline of 108b. Rural travel was down more than urban with rural interstates down 4.6% vs the urban interstates' decline of 3.0%. This apparently reflects the greater discretionary nature of rural travel and the hit taken by longdistance trucking from the sharp decline in the economy.

For the year as a whole regional discrepancies in travel are minor. The south-gulf dominated by Texas has suffered marginally less - down 3.6% vs northeast 5.0% down, west 5.4% down, north central 5.8% down and south atlantic down 6.1%.

see http://www.fhwa.dot.gov/ohim/tvtw/tvtpage.cfm

TOLLROADSnews 2009-02-23