Magnitude of Construction Cost and Schedule Overruns in Public Work Projects

Table 3

List of variables.

No.	Variable	Type of scale	Explanation
1	Type of project	Nominal	Either flood control, transportation, or utilities
2	Year	Interval	Project completion year
3	Engineer estimated cost	Ratio	Engineer’s estimated cost of project
4	Award cost	Ratio	Contract award cost of project
5	Change orders	Ratio	Cost of change orders issued in the project
6	Final cost	Ratio	Actual cost of the project
7	Cost overrun (%)	Interval	Difference between the actual and award cost divided by award cost
8	Construction days awarded	Ratio	Days awarded to complete the project
9	Construction days added	Ratio	Days added to complete the project
10	Schedule overrun (%)	Interval	Difference between actual and award days divided by award days
11	Notice to proceed (NTP) date	Interval	Construction start date
12	Substantial completion date	Interval	Construction completion date
13	Size of project	Ratio	Size of the project, as measured by the class of the actual cost converted to a 2008 base cost
14	Project construction duration	Ratio	Duration of the project, as measured by the class of the actual completion duration
15	Project completion year	Interval	Project completion year, as measured by the class of the actual project completion date