Peak Travel?

Call me a skeptic about the “peak oil” story. Human ingenuity has always found ways to produce more of, find substitutes for, or discover ways to do without a scarce resource when price signals tell us to. But if peak oil is true, doesn’t one good peak deserve another? Why not meet peak oil head on with its dreaded natural enemy: peak travel?

At the risk of oversimplification, American history in the 20th century basically comes down to four “C’s”: communications (phone and TV), computers, cars and contraception. Though a graph showing the impact of the pill on American mating habits might be more interesting, here’s one I pulled together on the colossal growth of driving over the course of the last century:

All this motion may cheer you, since travel is a prerequisite for many, many of the things that make life worth living: work, school, shopping, social life and entertainment, to name but a few. On the other hand, the graph tells a negative story too: with all that driving has come lots of congestion, crashes and CO2.

If the latter problems are your focus, there is hope: take a look at the far right side of the graph. The growth in VMT/person started to tail off in the year 2000, and contrary to everything history has taught us, from 2005 to 2008 VMT/person actually dropped each year. As of 2008, we were driving about the same amount per person that we were in 1998. (2009 numbers aren’t in my data set, but stats from the Federal Highway Administration show the phenomenon continued, with 2009 per capita travel below 2008 levels.)

Does the stagnation in car travel in the 2000s represent a statistical quirk, or evidence that a century of automania is coming to an end?

A pair of papers-one from Robert Puentes and Adie Tomer of the Brookings Institution, and one from researchers Adam Millard-Ball and Lee Schipper of Stanford University-have come out on this phenomenon. With their help, what can we speculate about the causes for and durability of the mysterious phenomenon of peak travel? More next time.

(HT: Brad Morris and Melinda Burns of Miller-McCune)


Is commercial trucking included in the index? I'd also like to see a cost/mile weighted index, as well as a speed/mile weighted one.

Frank Vasquez

The graph you posted suggests that consumers do cut back travel when energy becomes more expensive (look at 1973 and 1979) or unavailable (WWII).

I'd be curious to see if there are correlations with the aging of the population and unemployment (look at 1930). You would figure that people who are not commuting tend to drive fewer miles.

Michael Radosevich

This trend is good news. I wonder if the data exists to do a graph on walking. Based on anecdotal evidence, walking seems to be growing over the past twenty years.

Drill-Baby-Drill drill Team

In Pre Modern Times travel over 10 miles was excessive, risky and needed planning.

Joseph took his wife, who was heavy with child from Jerusalem to Bethlehem to comply with a new Roman Census. There was no room at the Inn. A whole production ensued involving shepherds, wise men, angels and a manger.

The actual distance from Bethlehem to Jerusalem: 8 miles. In modern times that would be the equivalent of two freeway exits.

In Biblical Times, the farthest a person ventured from their place of birth was 30 miles. Jesus was no exception.

Drill-Baby-Drill drill Team

European landscape was shaped by centuries of living with limited intercity transit accomplished by horses and wooden wheeled wagons. People rarely left their village, let alone their province or country. And each little geographic was cut off leading to hundreds of languages in an area the size of Texas.

Maybe America will once again be villagers who do not have the means to venture too far from their birthplace. And live for generations in a small area.

We need mass transit, high speed rail and reconsolidated dense cities as the Europeans and now the Chinese are advocating. Or we should resort to having horses and haywagons.

The END of OIL will occur in the lifetime of children currently present. They may be force to become villagers.


Today's column brought to you by the letter C.

I think part of what we are seeing is a ceiling on the amount of time people are willing to spend in the car. Since cars haven't gotten much faster (for safety reasons) over the last 40 yrs or so and the average highway speed actaully dropping (due to congestion), the only way to travel farther is to spend more time in the car. It seems more like a leveling-off than a peak.


Additional factors: Internet shopping means less trips out of the house. Increasing numbers of people are working from home. And, possibly, more home entertainment options and better entertainment systems mean less people are going out to movies, theater, sporting events, etc.

Greg Comlish

"Human ingenuity has always found ways to produce more of, find substitutes for, or discover ways to do without a scarce resource when price signals tell us to."

Except at Easter Island where the natives cut down all the trees upon which they were economically and ecologically dependent thus ushering in a major resource shortages, brutal tribal warfare, religious fanaticism, and the collapse of rational thought.

Ian Kemmish

What a pity that none of the graphs in the second paper have a time axis. (Let's hope the choice of axes reflects the authors' conclusions and not their preconceptions!)

This seems like a classic candidate for a "very large dataset" visualisation animation. Given that the trend started in the year 2000, my guess would be that mileage first started to decline in high technology areas, then spread to large conurbations, then to the rest of the country. You might have guessed that my pet explanation is the rise of telecommuting and Internet shopping.


Something about this graph leaves me confused. If persons (in VMT/person) is the total US populations, why is the ratio of VMT to VMT/person in 1930 ~ 500,000,000,000/1,000 or 500,000,000 million, but in 1980 ~ 3,000,000,000,000/10,000 or ~ 300,000,000?

Eric M. Jones



Luke 2:1 In those days Caesar Augustus issued a decree that a census should be taken of the entire Roman world. ....

4 So Joseph also went up from the town of Nazareth in Galilee to Judea...

Which is pretty cool because Nazareth DIDN'T EXIST!

Eric M. Jones

"In The Day"....we used to drive to the store to get things. Now we get it online and have it delivered. This really makes a HUGE difference in my travel. I am sure the price of gas figures in, but not as much.

I speculate that much of the conniptions of the economy are from the Baby Boomers going through the demographic snake. When we went to college, the colleges exploded, when we needed houses, the real estate market soared. Now we are retiring and the economy collapses. This driving thing could be one of those....

Oh yes, I remember driving fifty miles at night just to stalk whatever-her-name-was.


The premise that "Human ingenuity has always found ways to produce more of, find substitutes for, or discover ways to do without a scarce resource" is only true in the sense that the species hasn't gone extinct; there are historical examples of societies collapsing, presumably from depletion of resources.


The economy has gone more and more sour since 2000. The correlation is clear, there is a decline in vehicle miles traveled since 2000. What has happened to the greater economy since then? It has declined in real terms over the entire period. Do those other dips in the curve correlate to recessions as well? Two years ago we had a 2% undersupply of oil. Remember what happened to fuel prices? I believe the analysis of that graph is a bit simplistic, all things considered...

Peak travel and peak oil will necessarily correlate because there is currently nothing on the horizon to replace oil for portable energy storage. We literally can't grow enough ethanol, electricity for electric cars has to come from somewhere, supplies of natural gas are finite and, if used for transportation, will be depleted more rapidly than current, overly optimistic predictions so predicting peak oil and peak travel to coincide is much like correlating the tide to the position of the moon, a no-brainer.


Rob Lewis

A stunningly obtuse Pollyannaism is in evidence in your Peak Oil skepticism. As James Howard Kunstler has observed, techno-optimists stubbornly conflate the terms "technology" and "energy". Accustomed to Moore's-law-style leaps and bounds in performance, you fail to notice that a hard-won 3% improvement in the efficiency of a power plant is a Very Big Deal.

Since we are already at the tipping point of catastrophic climate change, if we discovered oceans of new oil tomorrow we'd be suicidal fools to burn it. And if we aren't suicidal fools-a questionable assumption, to be sure-the reality is that we're so far from having serious alternatives to fossil fuels running on the massive scale required that, one way or another, a Long Emergency (the title of Kunstler's book) is already baked into the cake.


Another factor at work: a decade ago I used to travel about 30 miles to and from work, every working day of the year, or about 7500 miles per year. Now, thanks to telecommuting, that's reduced to taking a few steps into my home office. (But, I admit, somewhat offset by the former workday afternoons that I travel to a trailhead somewhere :-))

Multiply that by a few million telecommuters, and it starts making a pretty noticable dent in vehicle miles travelled.

Mike B

Isn't it desirable for people not to NEED to travel to reach goods and services? Perhaps a better measure would be discretionary travel, ie travel that is not required to carry out the necessary functions of life such as commuting to work and school and shopping.

I don't know about you, but a society where everyone has to spend 2 hours a day in the car going to work has a lot of inefficiencies built in.


"Human ingenuity has always found ways to produce more of, find substitutes for, or discover ways to do without a scarce resource when price signals tell us to."

Ummm-- water? Many parts of the world have lost population to a lack of water (Peru, Timbuktu), or too much water (Tuvalu).

And there is a theory that the lack of protein (specifically large meat animals) was one reason for the abandonment of Mayan and other Central American cities.


How about the housing market upsets affecting where people live and thus how far their commutes are?


There is such thing as auto mania, its just a vehicle that facilitates long travelling distance and faster mobility to have more time for other things. Even though the graph shows a trend during the 2000s that the need for a car is decreasing does not mean that "auto mania" is coming to an end but its that there is more available substitutes such as trains or bus that would save you lots of money invested in a car (cleaning, gas, cars price).

Besides there being cheaper substitutes available there is the online virtual life were one can basically do anything via home. People do not have to stand up every morning and turn the car on when one has access of telecommunication were one can work from home and do all task. One does not need a car to shop nor grocery shop because it could be done as you sit in your living room with no car in the garage.