Here’s a very short OPB article. I downloaded the actual report, and gas use has dropped mostly because of less driving, not more fuel-efficient vehicles.
He explained, “Cars are getting a little bit more efficient, we’re tending to drive a little bit less. We are seeing gains in mass transit and alternative transportation, like bicycles. But really, behind all of these changes appears to be the rising and volatile price of gasoline.”
The report says that over the last 10 years, the miles driven per capita on state roads has fallen 13 percent; and vehicle fuel efficiency has increased a few percentage points.
As they mention, this calls into question not only the financing for major highway projects, but indeed the need for them.