Efficiency measures

This study examined the project management and construction phases of infrastructure programs, i.e. capital expenditure (capex), and defined procurement efficiency in terms of time and cost dimensions as follows:

•  Normalised time - was measured as the percentage change in the time taken to achieve the next milestone in a stage compared with the timing anticipated at the beginning of that stage. It is expressed as a percentage, where a positive percentage indicates a time over-run relative to normalised expectations, and a negative percentage indicates completion ahead of time.

•  Normalised cost - was measured as the percentage change in the cost incurred at the next milestone in a stage compared with the cost anticipated at the beginning of that stage. It is expressed as a percentage, where a positive percentage indicates a cost over-run (over-budget) relative to normalised expectations, and a negative percentage indicates completion of the stage under budget.