Long distance travel in Europe today: Experiences with a new survey

The paper discusses the problems of long distance travel surveys, with examples from recent studies, and presents results of a new long distance survey approach to overcome these problems. As part of of the 6 Framework funded KITE project (A Knowledge Base for Intermodal Passenger Travel in Europe), a new survey methodology based mainly on the MEST (Methods for European Surveys of Travel Behaviour) and INVERMO (Intermodale Vernetzung) surveys was developed and tested in three different European countries. The method starts with a journey roster of basic items for the long distance journeys undertaken and a stage form for details about the last three long distance journeys. First, a short overview of conventional household travel surveys of long distance travel is given, followed by a description about their main problems and the survey approach which was chosen to overcome these. The second part presents the long distance journey rates from the KITE surveys and presents corrected rates from a homogenous hazard-model for Switzerland, the Czech Republic and Portugal. These figures are compared with the results of the majority of long distance dedicated surveys. INTRODUCTION AND BACKGROUND Long distance travel is a growing travel market segment, but reliable data and statistics about long distance travel are rather rare. Information about long distance travel has to provide answers to many different questions. For transport policy, fares paid and costs incurred are central in the process of coordinating between different existing transport facilities and for the planning of new ones. Thus information about travel costs, prices of competitive modes and reasons for mode choice are absolutely required. In the context of transport planning, information about trip costs are equally useful as they provide insight into the cost structures, such as vehicle operating costs, user charges, taxes and tolls. Long distance travel data is especially needed for tourism, energy and environmental policies. Long distance travel is only in rare cases a part of daily mobility (e.g. salesmen or ambassadors). Therefore, such movements are reported with low frequencies in surveys of daily mobility at least for distances over 400 km (1). However national travel surveys (NTS) dedicated to daily mobility are the only source for long distance travel in many European countries (e.g. in Denmark or Netherlands). The problem with these surveys is the difficulty of obtaining representative statistics of long distance travel even with relatively big samples. Therefore, in most national travel surveys, additional modules are dedicated to long distance travel with the exceptions mentioned above. In addition to surveying mobility on a given day, the most common format in these surveys is to ask respondents to report their long distance journeys for a reporting period of four or more weeks (e.g. Great Britain NTS (2002-2004) (2), French NTS (1993-1994) (3), Swiss Microcensus on Travel Behavior (2005) (4), and Swedish RES (2005/2006) (5)). Surveys exclusively dedicated to long distance travel are a less frequent data source. But past surveys show very different levels of long distance travel demand for similar countries, which make those numbers hard to trust (e.g. DATELINE (6)) (1). Because of this data gap the European Commission funded KITE (A Knowledge Base for Intermodal Passenger Travel in Europe) which aims at providing information for stakeholders in the field of long distance intermodal travel (7). As mentioned above a central part of KITE was the development and test in a pilot survey of a suitable survey methodology that to close the remaining information gaps. These pilot surveys were carried out in Switzerland, the Czech Republic and Portugal to cover a range of languages and socio-economic conditions. First, an overview about available and comparable long distance travel surveys is given. The survey methodology of the KITE pilot survey is described next. Finally, the long distance demand figures are analyzed and compared with other data sources. AVAILABLE LONG DISTANCE TRAVEL DATA FROM HOUSEHOLD SURVEYS The survey work within KITE is a conventional household travel survey. In contrast to other survey approaches (e.g. mobile phone tracking, ticket sale figures, credit card payments on highway toll booths or cross border counts (8)), which provide only information on one particular facet of long distance travel activity, conventional household travel surveys give additional information, which is crucial for understanding and modeling individual long distance travel activities (9). Frei, Kuhnimhof, Axhausen 3 TABLE 1 gives an overview of available household surveys with information on long distance travel, which are later used to compare the results from the KITE pilot surveys. For a more comprehensive overview see (1). It covers two types of surveys: Mobility diary surveys (National Travel Surveys) with a focus on every day travel, and surveys dedicated to long distance travel. In the following, a brief overview describes the characteristic problems of long distance surveys in general and the characteristics of the surveys in TABLE 1. General problems of long distance travel surveys The core of the design problem of long distance travel surveys is their exclusion of journeys below a minimum distance or duration. The movements to be reported are rare events requiring long reporting periods to increase the chance that the respondent can report at least one journey and that the contact is not wasted in terms of capturing information about travel. Counterbalancing this is the problem of recalling events, which might have happened weeks ago, in some detail, which limits the reporting period to a range of four to eight (twelve) weeks, given the relatively low salience of routine long distance travel for many above average frequency travelers (15). Long distance Travel Definitions In surveys of daily mobility, the study objective is clear: capture all movements of the respondents for a day, excluding only movements within large facilities, such as shopping centers or factories. Even this basic question is open to discussion in the case of long distance travel. Because the division between movements relevant to long distance travel, the related decision making and the irrelevant local movements needs to be defined, as it is impossible to ask the respondents to report all movements undertaken during a multi-day long distance journey (See (14) for a more thorough discussion). Tourism and transport planning are the two main focuses of long distance travel surveys. On the one hand it is possible to differentiate long distance travel from daily mobility by the duration of being away from home; on the other hand it is possible to define it by a minimum distance travelled from a certain base location. While the duration of a stay is the main focus when looking at tourism where data is needed for supply and marketing decisions, the duration of stay is not crucial for transport planning, where the data need is more focused on route/mode choices which are determined in part by distance. The decision to use distance as a criterion is widely accepted in transport planning long distance surveys, but the exact cut-off and type of TABLE 1 Analyzed household travel surveys with information on long distance travel (11,12,4,6,13,14) Survey Spatial Coverage Survey Year Everyday Travel Diary Long Distance Travel Definition Long Distance Travel Reporting Period INVERMO Germany 1999-2002 No >100 km network 8 weeks MiD Germany 2002 Yes Overnight stay 12 weeks Micro Census Switzerland 2005 Yes Excursions > 3 h overnight stay 2 weeks 8 weeks DATELINE EU 15 + CH 2001/02 No >100 km crow-fly (holiday journeys) 12 months (other journeys) 3 months MEST/TEST France, Portugal, Sweden, UK 1996/97 No >100 km crow-fly 8 weeks KITE Switzerland, Czech Republic, Portugal 2008/09 No >100 km crow-fly 8 weeks Frei, Kuhnimhof, Axhausen 4 distance (crow-fly or network distance) were never harmonized and vary from country to country and survey to survey. For the analysis in this paper, long distance journeys are defined as journeys including outbound trip and return trips to destinations at crow-fly distances of at least 100 km. We adopted this definition because it is the EUROSTAT definition which was used in the DATELINE survey, and DATELINE was the only Europe wide survey so far. In some surveys crow-fly distances were not available (German MiD, German INVERMO). In these cases we corrected reported distance to be network distance and recalculated crow-fly distances using observed detour factors (Germany: 1.28 (16)). In the case of travel diary surveys with focus on everyday travel, we first analyzed single trips and then calculated the number of journeys based on the assumption that one long distance journey includes two long distance trips.