How Americans Travel to Work

By C. Kenneth Orski
for eco-logic/Powerhouse

November 03, 2006

How have commuting travel patterns evolved over the last decade? Is our dependency on the private automobile growing or lessening? How about carpooling and transit usage? What has been the impact of immigration and the changing nature of the workforce? What are "extreme commutes?" You will find the answers to these and hundreds of other travel-related questions in the latest edition of "Commuting in America," the third and latest decennial analysis of the nation’s work travel trends, authored by Alan Pisarski and published by the Transportation Research Board (TRB).

According to the latest TRB report on commuting, travel to work accounts, surprisingly, for only 15 percent of all daily person trips (down from 20 percent in 1990). The rest is made up of a myriad other trips. The decline in share, as the report points out, is not so much due to any decline in work travel but rather to a more rapid growth in other trip purposes: personal business travel, social/recreational travel, school travel, etc. As incomes rise, total daily trips per person increase while work trips remain constant. Thus, work trips as a proportion of total trips have been declining.

So, is the emphasis on commuting still appropriate? The answer is yes. For it is the impact of commuter travel that generates the headlines, dominates radio waves during "drive time," determines highway capacity and performance requirements, influences transportation planning, and drives transportation investment decisions. It does all these things for one simple reason: the twice-daily commute to and from work is highly peaked (almost two-thirds of all morning trips to work occur between 6-9 a.m.) and is concentrated in defined travel corridors. Because of its concentration in time and space, travel to work is the source of most delays and traffic congestion. It is also the travel experience that people most complain about and thus is an issue that gets the politicians’ attention.

Those who hoped to find in the report signs of a waning of Americans’ dependency on the auto came away disappointed. All car-oriented indicators – growth in total automobile population (30 million vehicles added in the 1990s), number of car-owning households, vehicles per household, use of the automobile – continued their upward trend throughout the last two decades of the 20th century.

Here are the salient facts as reported in Commuting in America III:

Driving alone to work continues to increase its dominance in commuting behavior. Since 1980, the number of solo commuters increased by more than 11 percentage points. In the 1990s alone, the number of new drive-alone commuters grew by almost 13 million; it now accounts for 78 percent of all workers according to the Census Bureau’s 2004 American Community Survey.

Carpooling share declined by 7.5 percentage points during the same period and now accounts for 10 percent (as contrasted with 20 percent in 1980). Two-person carpools constitute 77 percent of the total. Most of them involve family members – "fam-pools" as Pisarski calls them.

Transit usage gained in some areas, lost in others, but basically remained flat during the last 20 years. It currently accounts for 4.6 percent nationwide but shows significant variations according to the size of metropolitan area. For example, transit share of total commuting stands at 19 percent in metro areas of 1-5 million, and as high as 35 percent in metro areas over 5 million. Work at home (aka telecommuting), which was insignificant back in the 1980s, now stands at a statistically significant 3.8 percent. The number of those who work at home increased by 2 million workers, almost doubling in the period 1980-2000, according to Pisarski who calls this trend "the quiet revolution."

Finally, walking to work has suffered a sharp decline and now accounts for only 2.4 percent of work trips, as contrasted with 5.6 percent in 1980. It’s a reality check for those who claim to see a trend toward "walkable communities."

The explanation behind these statistics is not difficult to divine. Despite the entreaties of smart growth advocates, population and employment continue to disperse, making auto travel the most convenient — often the sole — means of commuting. The report finds that commuting from suburb to suburb — where the auto is practically the only means of transportation available — continued to increase as a proportion of total metropolitan commuting during the decade of the 1990 and stood at 46 percent of all work trips in 2000. On the other hand, the traditional commute from the suburbs to the central city — where transit can play an important role — dropped in share from 20 percent in 1990 to 19 percent in 2000.

Not only is population dispersing, it is dispersing farther and farther out, leapfrogging over existing suburbs. This has led to a new phenomenon — the "extreme commute." This is commonly defined as commutes exceeding 90 minutes each way. The 2000 Census identified about 3.5 million commuters, roughly 2.8 percent of workers, as extreme commuters. Eight metropolitan areas have more than two percent of workers with one-way commutes of over 90 minutes. (Baltimore, New York, Newark, Riverside, CA, and Los Angeles top the list.) While extreme commutes still make up a relatively insignificant share of total trips, their proportion is likely to grow as more and more people migrate farther and farther out in search of greater living space and more affordable housing.

There is much, much more in this fact-filled report. Meticulously documented and profusely illustrated with graphs and charts, Commuting in America III presents a fascinating snapshot of the changing travel patterns and travel behavior in contemporary America. Just as its preceding editions, the report will surely become the definitive source of data and analysis on commuter trends. Alan Pisarski and the Transportation Research Board deserve our thanks for this valuable contribution to our understanding of how Americans travel to work.

Commuting in America III: The Third National Report on Commuting Patterns and Trends, NCHRP Report 550, Transportation Research Board, October 2006. Copies can be ordered on the Internet.

Reprinted from Innovation Briefs, November/December 2006.

C. Kenneth Orski is the Editor/Publisher of Innovation Briefs
10200 Riverwood Drive
Potomac, MD 20854
tel: 301.299.1996
fax: 301.299.4425