VMT Growth Rates Highway Performance Monitoring System (HPMS) versus Gasoline Sales

1. VMT Growth RatesHighway Performance Monitoring System (HPMS) versus Gasoline Sales Transportation Work Group Phase III - Meeting 3 February 25, 2004 410-569-0599 www.meszler.com

2. Transportation Plan 2020 - HPMS “The most recent 10 years of HPMS data was evaluated and an average yearly growth rate was calculated. This average yearly growth rate was 2.0828 percent.” (Appendix A) Page 2

3. Regression Results (RI Data) Linear trends are tied to a base year (e.g., a 1970-2000 linear trend means that the annual VMT change is X percent of 1970 VMT, not X percent of the preceding year VMT). Page 3

4. Regression Results (FHwA Data) Linear trends are tied to a base year (e.g., a 1970-2000 linear trend means that the annual VMT change is X percent of 1970 VMT, not X percent of the preceding year VMT). Page 4

5. 10 Year Period HPMS Growth Rates Annual rates dropped below 2 percent in the late 1990’s, bottoming out in the 10 year period ending 1998. Page 5

6. 11 Year Period HPMS Growth Rates Annual rates dropped below 2 percent in the late 1990’s, still exhibiting a small decline through the 11year period ending 2000. Page 6

7. Gasoline Sales Trends Page 7

8. Gasoline Sales Trends vs. HPMS Page 8

9. Summary Page 9

10. Conclusions • Trends are in pretty reasonable agreement given the cursory level of analysis. • Factors such as changing fuel efficiency, offroad equipment gasoline sales, through-travel/refueling effects, etc. are likely to explain differences. • Initial concern over large discrepancy between gasoline sales and HPMS trends appears to be unfounded, but likelihood of negligible future VMT growth also doubtful. Page 10