Evidence review of car traffic levels in Britain

This study presents findings of a rapid evidence assessment of literature to understand the factors and trends influencing the recent levelling off in total miles driven in Britain since the 1990s. We find that the literature provides a good description of trends influencing car mileage; including: (i) changes in traditional economic factors, including fuel price increases and income growth, (ii) reductions in driving levels for young people, (iii) population increases in urban areas, where car ownership and car use levels are lower (although the impact of growing population in conurbations and cities on per capita car mileage appears to be relatively small), (iv) increasing levels of car travel for women, although women are observed to still drive less than men, (v) that the elderly drive less than other population groups, although their car mileage is also increasing, (vi) increased immigration levels, although migrants are observed to use their cars less than the those born in Britain, even after taking account that migrants tend to live in urban areas, (vii) reductions in company car ownership, and associated reductions in car mileage, particularly for men. However, the size of many of these trends on overall car mileage levels, and the drivers impacting these trends, are less clear. We found little information on how the following trends impact car travel: (i) employment levels or type, (ii) use of internet technology, (iii) substitutes, in terms of mode shifts or switching to new destinations, (iv) network supply effects, such as congestion, and (v) attitudinal changes.