Some Facts Related to Mobility and Sprawl

Below are some facts from a chapter called Mobility and Sprawl in Bowling Alone, published in 2000. While these facts are dated and national in scope, they reveal behavior trends that continue to this day, and impact local traffic and parking. Rather than draw conclusions here, I’ll post more about this soon.

Smaller Households with More Cars

  • for decades the number of single-occupancy vehicles in use has increased
  • we’ve gone from 1 car per household to nearly 2 per household in 1995
  • this is remarkable considering the household size has shrunk from 3.6 to 2.6 members
  • by 1990, America had more cars than drivers

We Invest More in Our Cars

  • between 1969 and 1995, we increased our financial and time investments in cars
  • the length of the average commute increased 26%
  • the length of the average shopping trip increased 29%
  • the number of commuting trips per household increased 24%
  • the number of shopping trips per household almost doubled
  • the number of other trips for personal or family business more than doubled

Passenger Occupancy has Declined 50%

  • during this same quarter-century, each trip was more likely to be made alone
  • the average vehicle occupancy fell from 1.9 in 1977 to 1.6 in 1995
  • for trips to and from work, the average occupancy fell from 1.3 to 1.15
  • by definition, vehicle occupancy cannot fall below 1
  • therefore this represents a 50% occupancy decline in passenger commuting

Some Commuting Data

  • commuting accounts for a little more than one-quarter of all personal trips
  • but given the structure of our lives, it is the single most important trip of the day
  • the number of people working from home has risen
  • however the proportion of home workers to total workers remains tiny (< 4% in 1997)
  • the % of people who drive to work alone has risen from 61% in 1960 to 91% in 1995
  • other modes of commuting – public transport, walking, etc. – have all declined
  • mass transit plays a small, declining role in most major metros
  • mass transit accounted for only 3.5% of all commuting trips in 1995

Some Carpooling Data

  • carpooling has also fallen steadily for more than two decades
  • the fraction of all commuters who carpool has been cut in half since the mid-1970s
  • this fraction is projected to reach only 7-8% by 2000
  • bottom line: by end of the 1990s, 80-90% of all Americans drove to work alone
  • this is a major increase over the 64% who drove to work alone as recently as 1980

We’re Commuting Farther

  • we are commuting farther than ever before
  • from 1960 to 1990, the # of workers who cross county lines more than tripled
  • between 1983 and 1995, the average commuting trip grew 37% longer in miles
  • ironically, travel time increased by only 14%

We’re Commuting Faster

  • travel time increased by < trip length because average speeds increased
  • the average speed of all modes of transport combined increased by nearly 25%
  • the switch from carpools to mass transit to SOVs was quicker for individual workers
  • however the switch has been socially inefficient
  • suburb-to-suburb commuting increased
  • work hours became more flexible

We’re Alone Longer in Our Cars

  • 68 urban areas were studied, from LA to Corpus Christie to Cleveland to Providence
  • annual congestion-related delay per driver rose steadily from 1982 to 1997
  • the delay per driver rose from 16 hours in 1982 to 45 hours in 1997
  • many see this as a time for quiet relaxation
  • this is especially true for those who came of age during this driving boom
  • according to one survey in 1997, 45% of all drivers agreed that “driving is my time to think and enjoy being alone”
    • among drivers aged 18 to 24, 61% agreed with this statement
    • among drivers aged 55 and over, 35% agreed with this statement