A Comparative Study of Commuter Patterns and Trends in Great Britain, Ireland and the US
I Williams, Indpependent Consultant, UK
Commuting patterns and trends in Great Britain, Ireland and US are analysed to improve our forecasting ability and understanding of commuting behaviour in a period of economic stagnation and congested urban roads.
The commuter trip is still the major user of road and rail capacity in congested peak periods so that forecasting the future pattern of commuter travel is a critical task for most urban passenger models.
Patterns of commuting have changed through time but these changes do not follow simple linear trends. In many countries the long-run trend of increases in commuting trip lengths in the last century has eased in the last decade. The influences that generate changes in commuting patterns are examined in this empirical study.
To provide a laboratory for these investigations commuter patterns and trends within Great Britain are contrasted between the rapid service industry based economic growth in London and the South East versus the much slower economic growth in the heavy industry based economy of the West Midlands region. These analyses are based on the commuter patterns observed in the spatially detailed decennial Census, and in a more aggregate fashion but on an annual basis in the National Travel Survey (NTS) and the Labour Force Survey.
Commuting patterns and trends in Ireland and the US are analysed to see what light they shed on behaviour in Great Britain. Since 1981 Ireland has collected detailed commuter travel data at 5-yearly intervals. This covers both the economically depressed decade up to 1991, which had 17% growth in trip length, and the subsequent very rapid urban population and economic growth in the 16-year ?Celtic tiger? era up to 2007. This latter period exhibited 48% trip length growth in the 11 years to 2002 but no growth in the subsequent 4 years by which time road congestion had grown substantially. Similarly in the US the significant decline in car speeds over the last decade in the congested larger metropolitan areas has been associated with a change in trend there to a reduction in the average commuter distance travelled in order to compensate for the extra travel time needed.
Factors that influence trends in commuting patterns which are examined across one or more of the study regions include:
- The effect of travel speed (either by car or public transport) and congestion on travel distance
- Trends in car ownership, car operating costs and public transport fares
- Change in industrial structure ? the growth in specialised business and professional service jobs and the decline in manufacturing and in unskilled jobs
- Change in the balance of males to females in the workforce
- Change in the balance of full-time to part-time
- Planning policy to encourage higher density urban residential development
- Planning policy on out of town office and retail employment
- Local imbalances for individual segments of the labour force between the labour supply and demand
- The potential impact of growth in tele-working
- Trends in multi-stage commuting trips (e.g. initial leg being escort to school).
The aim is to provide guidance on how to improve trip distribution models for the commuting trip purpose. This would enable improved forecasts of both future peak-hour travel demand and of its responsiveness to policy levers.
Association for European Transport