The project summary information form was designed to record both qualitative and quantitative data. The qualitative data was required to provide background information on the project and expand on project risk areas that have had an impact on the project. A large proportion of the qualitative data has not been used in the analyses. A blank template of the form used to capture summary information for the projects studied (the project summary information form) is included in Appendix D.
The key quantitative data required for the optimism bias analyses are as follows:
• Business case (BC) date and contract award (CA) date
• Works start and end dates as planned at BC and CA
• Actual works start and end dates
• Capital expenditure as planned at BC and CA
• Actual capital expenditure
• Operating expenditure as planned at BC and CA
• Actual operating expenditure
• Unitary payments at BC and CA
• Actual unitary payments
• Benefits shortfall (expressed as a percentage of benefits planned at BC).
In addition to the key data listed above, five project risk groups, each divided into a number of project risk areas have been identified. The list of project risk areas along with brief explanations can be found in Appendix E.
The five project risk groups identified in the Mott MacDonald study are as follows:
• Procurement related
• Project specific
• Client specific
• Environmental
• External.
For each of the optimism bias levels measured (time, capital and operating expenditures, unitary payments and benefits shortfall) a total score of 100% has been allocated amongst the project risk areas, with a view to determining their relative impacts on the optimism bias.