Desviaciones de costos

Transport Policy 22 (2012)  49–56[pic 1][pic 2][pic 3][pic 4]

[pic 5]

Characteristics of cost overruns for Dutch transport infrastructure projects and the importance of the decision to build and project phases

C.C. Cantarelli a,n,1, E.J.E. Molin b, B. van Wee b, B. Flyvbjerg c

a Oxford University, BT Centre for Major Programme Management, Sa¨ıd Business School, Park End Street, Oxford OX1 1HP, UK

b Department of Transport and Logistics, Delft University of Technology, Faculty Technology, Policy and Management, Jaffalaan 5, NL-2628 BX Delft, The Netherlands.

c Oxford University, BT Centre for Major Programme Management, Sa¨ıd Business School, Park End Street, Oxford OX1 1HP, UK

[pic 6]

a r t i c l e  i n f o  

Available online 19 June 2012        [pic 7]

Keywords: Cost overruns Transport Infrastructure Project phases Netherlands

ELa b s t r a c t  

[pic 8]

Using a methodology similar to that used the in the worldwide research, the cost performance of Dutch large-scale transport infrastructure projects is determined. In the Netherlands, cost overruns are as common as cost underruns but because cost overruns are larger than cost underruns projects on average have a cost overrun of 16.5%. The focus on one country further enabled to consider cost overruns during different project development phases. It turned out that in the Netherlands the majority of the cost overrun occurs in the pre-construction phase (the period between the formal decision to build and the start of construction). The frequency as well as the magnitude of pre- construction cost overrun is significantly higher than in the construction phase. The used methodology of calculating cost overruns does however not take lock-in into account. This phenomenon shows that the real decision to build was taken much earlier in the decision-making process. Since estimated costs are usually lower during these earlier stages, the cost overruns based on this real decision to build are likely to be much higher. Cost overruns presented in studies are therefore often underestimated and the problem of cost overruns is much larger than we   think.

&  2012 Elsevier Ltd. All rights reserved.[pic 9][pic 10]

1. Introduction

Transport infrastructures are expensive and often involve large cost overruns. Projects become more expensive than was initially estimated and additional budget is required. Consequently, as the total budget for infrastructure investments is generally fixed, the budget to cover the costs of other projects is insufficient. Cost overruns therefore not only result in financial consequences for the project under consideration but also ultimately in fewer infrastructure projects being realised than planned. The problem of cost overruns is even more disturbing considering the fact that ‘‘cost escalation has not decreased over the past 70 years’’ (Flyvbjerg et al., 2003b).

The problem of cost overruns is thus severe and persistent and probably affects every country investing in transport infrastruc- ture. The question, however, is to what extent. The study by Flyvbjerg et al. (2002, 2003a, 2004) can be considered the leading piece of research into cost overruns because of the large number of projects included, the variety of project types, the long time

[pic 11]

n Corresponding author. Tel.: þ44 1865 288482.

E-mail address: Chantal.Cantarelli@sbs.ox.ac.uk (C.C. Cantarelli).

1 Formerly at: Department of Transport and Logistics, Delft University of Technology, Faculty Technology, Policy and Management, Jaffalaan 5, NL-2628 BX Delft, The Netherlands.

period and the wide geographical coverage. However, the results of this study do not necessarily apply for individual countries. For example, the conclusions for Europe do not necessarily apply to each individual European country.

Several studies on cost overruns have focused on individual countries. Table 1 gives an overview of these studies on cost overruns, their geographical area, the frequency and the magni- tude of cost overruns. The study of Flyvbjerg et al. (2003a) is included in the table for reasons of comparison. Note that these studies measure cost overruns slightly differently, which is explained a few lines below the table.

All of these studies show that cost overruns are more common than cost underruns, with frequencies ranging between 52% and 95%. Conversely, the magnitude of the cost overruns differs between the studies. As for the differences in average cost over- runs between studies, the following main explanations can be given. First of all, the main reason for the differences in the average cost overrun between studies is the difference in the use of nominal and real prices (Flyvbjerg, 2007). Secondly, the way data are handled can explain the differences in the extent of cost overruns between studies (see for a more extensive elaboration Flyvbjerg et al., 2003b). Studies use different moments for the year of decision to build and the year of completion as the basis for the estimated and actual costs, and hence the extent of the cost overruns differs. Thirdly, differences can also be related  to

0967-070X/$ - see front matter & 2012 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.tranpol.2012.04.001

50        C.C. Cantarelli et al. / Transport Policy 22 (2012)  49–56

Table 1

Frequency and magnitude of cost overruns found in literature a.[pic 12]

Study        Geographical area        Frequency cost overrun (%)        Magnitude of cost overrun

a In which: %: the percentage cost overrun and N: the number of projects with cost  overruns.

...