Schedule Updating and Project Control - Construction Project Scheduling and Control - page 188

Most of the methods that are applied to find out the percent complete of an entire
project are the same as those explained earlier for calculating the percent complete for
individual activities:

1. Units completed: This method may work for the percent complete of an activ-
ity, but it is difficult to apply to the entire project because there is no single
unit in common to measure. An exception to this statement is a project with
simple and identifiable units of measure, such as earthwork, road pavement,
and sidewalk construction. We can say, for example, that 82 miles of a total
250 miles are completed. Then, the percent complete is 82/250, or 32.8%. In
this case, we are assuming that “a mile is a mile” in the project (i.e., all paving
effort takes the same amount of effort and duration throughout the project).
We may still have a problem with “partially finished” units, but the project
manager can make an assumption with a small error or apply the incremental
milestones method.
Other types of projects, such as residential, commercial, and industrial
projects, do not have a common unit of production. Do not confuse this “unit”
(a unit of measurement, such as a cubic yard of concrete, a linear foot of electric
wiring, or a square yard or foot of flooring) with “functional units” (finished
usable units, used mostly for design and estimating, such as a room in a hotel;
a bed in a hospital; a pupil in a school; millions of gallons of water per day,
or MGD, in a water project; and the like). Functional units must go through
multistage activities to get into their final form, and they are not appropriate,
in most cases, as a measure of work progress or project percent complete.
2. Cost/budget: The cost method is actually two methods, and it is a good idea
to combine them for comparison:

2.1 Baseline Cost/Budget Method: Percent complete = Budgeted cost to
date/Baseline budget
2.2 Actual Cost/Budget Method: Percent complete = Actual cost

to

date/Estimated cost at completion

Baseline ratio represents percent complete that is supposed to be achieved
at this point.
3. Man-hours: This method is similar to the previous one except that we use
man-hours in the equation. Obviously, this method produces a number that is
focused on labor man-hours (directly related to productivity), while the cost
method calculates percent complete based on total cost including labor, mate-
rials, and other things.

3.1 Baseline Man-Hour Method: Percent complete = Budgeted man-hours
to date/Baseline man-hours
3.2 Actual Man-Hour Method: Percent complete = Actual man-hours to
date/Estimated man-hours at completion