There's a far more effective way of reducing pollution and dependency on oil than buying more efficient cars or going electric: Driving less.
It's not an option available to everyone of course, but it certainly helps reduce fuel use. And it's something Americans have been doing in a steady trend since 2005.
That's according to data from StreetFilms (via Treehugger), whose video neatly illustrates how Americans, per-capita, have been driving less over the last eight years.
Several factors could have played a part in this, and it's likely a combination of variables is responsible, but no single factor is to blame.
The trend started before the recession, for example, so the global financial crisis of 2008-2009 didn't start the downward movement. Nor did rising gas prices, given the graph shows lower car use despite a large drop in gas prices during the mid to late 2000s.
Others point to younger people lacking interest in cars and driving. That's certainly something the car industry is worried about, and it's also something that the rising cost of driving plays a very real part in.
We've seen surveys which suggest young people care more about their internet access than they do their cars. And the rise of car-sharing services heavily targets those younger users who may have a license, but can't afford to run their own car (rather than those who simply aren't interested).
The video's data shows how annual miles traveled in cars among 16 to 34-year olds dropped 23 percent from 2001 to 2009. Younger people are still getting about, they're just doing it in other ways. As are older people, with 1.1 million seniors giving up their licenses between 2001-2009.
There's a message behind all this, which is that transport planners still develop strategies based on the assumption that car transport is rising. Instead, StreetFilms proposes, they should be planning for a populus moving away from driving, and invest in better infrastructure for walking, cycling and public transit.
For some people, driving will only ever be the sole realistic option. But in cities in particular, it makes more sense to plan for future where people simply won't be driving as much.