Chapter 7
Project Cost Management
Project Cost Management includes the processes required to ensure
that the project is completed within the approved budget. Figure 7-1 provides
an overview of the following major processes:
7.1 Resource
Planning—determining what resources (people,
equipment, materials) and what quantities of each should be used to perform
project activities.
7.2 Cost
Estimating—developing an approximation
(estimate) of the costs of the resources needed to complete project activities.
7.3 Cost
Budgeting—allocating the overall cost estimate
to individual work activities.
7.4 Cost Control—controlling changes to the project budget.
These processes interact with each
other and with the processes in the other knowledge areas as well. Each process
may involve effort from one or more individuals or groups of individuals, based
on the needs of the project. Each process generally occurs at least once in
every project phase.
Although the processes are presented
here as discrete elements with welldefined interfaces, in practice they may
overlap and interact in ways not detailed here. Process interactions are discussed
in detail in Chapter 3.
Project cost management is primarily
concerned with the cost of the resources needed to complete project activities.
However, project cost management shouldalso consider the effect of project
decisions on the cost of using the project’s product. For example, limiting the
number of design reviews may reduce the cost of the project at the expense of
an increase in the customer’s operating costs. This broader view of project
cost management is often called life-cycle costing. Lifecycle costing
together with Value Engineering techniques are used to reduce cost and time,
improve quality and performance, and optimize the decision-making.
In many application areas, predicting
and analyzing the prospective financial performance of the project’s product is
done outside the project. In others (e.g., capital facilities projects),
project cost management also includes this work. When such predictions and
analyses are included, project cost management will include additional
processes and numerous general management techniques such as return on
investment, discounted cash flow, payback analysis, and others.
Project cost management should
consider the information needs of the project stakeholders different
stakeholders may measure project costs in different ways and at different
times. For example, the cost of a procurement item may be measured when
committed, ordered, delivered, incurred, or recorded for accounting purposes.
When project costs are used as a component of a reward
and recognition system (discussed in Section 9.3.2.3), controllable and
uncontrollable costs should be estimated and budgeted separately to ensure that
rewards reflect actual performance.
On some projects,
especially smaller ones, resource planning, cost estimating, and cost budgeting
are so tightly linked that they are viewed as a single process (e.g., they may
be performed by a single individual over a relatively short period of time).
They are presented here as distinct processes because the tools and techniques
for each are different. The ability toinfluence cost is greatest at the early
stages of the project, and this is why early scope definition is critical, as
well as thorough requirements identification and execution of a sound plan.
7.1 RESOURCE PLANNING
Resource planning involves determining what physical
resources (people, equipment, materials) and what quantities of each should be
used and when they would be needed to perform project activities. It must be
closely coordinated with cost estimating (described in Section 7.2). For
example:
·
A
construction project team will need to be familiar with local building codes. Such
knowledge is often readily available from local sellers. However, if the local
labor pool lacks experience with unusual or specialized construction techniques,
the additional cost for a consultant might be the most effective way to secure
knowledge of the local building codes.
·
An
automotive design team should be familiar with the latest in automated assembly
techniques. The requisite knowledge might be obtained by hiring a consultant,
by sending a designer to a seminar on robotics, or by including someone from
manufacturing as a member of the team.
7.1.1 Inputs to Resource Planning
.1 Work breakdown
structure. The work breakdown structure (WBS,
described in Section 5.3.3.1) identifies the project deliverables and processes
that will need resources, and thus is the primary input to resource planning.
Any relevant outputs from other planning processes should be provided through
the WBS to ensure proper control.
.2 Historical
information. Historical information regarding
what types of resources were required for similar work on previous projects
should be used if available.
.3 Scope statement. The scope statement (described in Section 5.2.3.1)
contains
the project justification and the project objectives, both of
which should be considered
explicitly during resource planning.
.4 Resource pool description. Knowledge of what resources (people, equipment,
material)
are potentially available is necessary for resource planning. The
amount of
detail and the level of specificity of the resource pool
description will vary. For
example, during the early phases of an engineering design project,
the pool may
include “junior and senior engineers” in large numbers. During
later phases of the
same project, however, the pool may be limited to those
individuals who are knowledgeable
about the project as a result of having worked on the earlier
phases.
.5 Organizational policies. The policies of the performing organization
regarding
staffing and the rental or purchase of supplies and equipment must
be considered
during resource planning.
.6 Activity duration estimates. Time durations (described in Section 6.3.3.1).
7.1.2 Tools and Techniques for Resource Planning
.1
Expert judgment. Expert judgment will
often be required to assess the inputs to this process. Such expertise may be
provided by any group or individual with specialized knowledge or training, and
is available from many sources including:
·
Other
units within the performing organization.
·
Consultants.
·
Professional
and technical associations.
·
Industry
groups.
.2
Alternatives identification.
Alternatives identification is discussed in Section 5.2.2.3.
.3
Project management software.
Project management software has the capability to help organize resource pools.
Depending upon the sophistication of the software, resource availabilities and
rates can be defined, as well as resource calendars.
7.1.3 Outputs from Resource Planning
.1
Resource requirements. The
output of the resource planning process is a description of what types of
resources are required and in what quantities for each element at the lowest
level of the WBS. Resource requirements for higher levels within the WBS can be
calculated based on the lower-level values. These resources will be obtained
either through staff acquisition (described in Section 9.2) or procurement
(described in Chapter 12).
7.2 COST ESTIMATING
Cost estimating involves
developing an approximation (estimate) of the costs of the resources needed to
complete project activities. In approximating cost, the estimator considers the
causes of variation of the final estimate for purposes of better managing the
project.
When a project is
performed under contract, care should be taken to distinguish cost estimating
from pricing. Cost estimating involves developing an assessment of the likely
quantitative result—how much will it cost the performing organization to
provide the product or service involved? Pricing is a business decision—how
much will the performing organization charge for the product or service—that
uses the cost estimate as but one consideration of many.
Cost estimating includes identifying and considering various
costing alternatives. For example, in most application areas, additional work
during a design phase is widely held to have the potential for reducing the
cost of the productionphase. The cost-estimating process must consider whether
the cost of the additional design work will be offset by the expected savings.
7.2.1 Inputs to Cost Estimating
.1
Work breakdown structure. The
WBS is described in Section 5.3.3.1. It is used to organize the cost estimates
and to ensure that all identified work has been estimated.
.2
Resource requirements.
Resource requirements are described in Section 7.1.3.1.
.3
Resource rates. The individual or group
preparing the estimates must know the unit rates (e.g., staff cost per hour,
bulk material cost per cubic yard) for each resource to calculate project
costs. If actual rates are not known, the rates themselves may have to be
estimated.
.4
Activity duration estimates.
Activity duration estimates (described in Section 6.3.3.1) will affect cost
estimates on any project where the project budget includes an allowance for the
cost of financing (i.e., interest charges).
.5
Estimating publications. Commercially
available data on cost estimating.
.6
Historical information.
Information on the cost of many categories of resources is often available from
one or more of the following sources:
·
Project
files—one or more of the organizations involved in the project may maintain
records of previous project results that are detailed enough to aid in
developing cost estimates. In some application areas, individual team members
may maintain such records.
·
Commercial
cost-estimating databases—historical information is often available
commercially.
·
Project
team knowledge—the individual members of the project team may remember previous
actuals or estimates. While such recollections may be useful, they are
generally far less reliable than documented results.
.7
Chart of accounts. A chart of accounts
describes the coding structure used by the performing organization to report
financial information in its general ledger. Project cost estimates must be
assigned to the correct accounting category.
.8
Risks. The project team
considers information on risks (see Section 11.2.3.1) when producing cost
estimates, since risks (either threats or opportunities) can have a significant
impact on cost. The project team considers the extent to which the effect of
risk is included in the cost estimates for each activity.
7.2.2 Tools and Techniques for Cost
Estimating
.1 Analogous
estimating. Analogous estimating, also called top-down
estimating, means using the actual cost of a previous, similar project as
the basis for estimating the cost of the current project. It is frequently used
to estimate total project costs when there is a limited amount of detailed
information about the project (e.g., in the early phases). Analogous estimating
is a form of expert judgment (described in Section 7.1.2.1).
Analogous estimating is generally less costly than other
techniques, but it is also generally less accurate. It is most reliable when a)
the previous projects are similar in fact and not just in appearance, and b)
the individuals or groups preparing the estimates have the needed expertise.
.2 Parametric
modeling. Parametric modeling involves using
project characteristics (parameters) in a mathematical model to predict project
costs. Models may be simple (residential home construction will cost a certain
amount per square foot of living space) or complex (one model of software
development costs uses thirteen separate adjustment factors, each of which has
five to seven points on it).
Both the cost and accuracy of
parametric models vary widely. They are most likely to be reliable when a) the
historical information used to develop the model was accurate, b) the
parameters used in the model are readily quantifiable, and c) the model is
scalable (i.e., it works as well for a very large project as for a very small
one).
.3 Bottom-up
estimating. This technique involves estimating
the cost of individual activities or work packages, then summarizing or rolling
up the individual estimates to get a project total.
The cost and accuracy of bottom-up
estimating is driven by the size and complexity of the individual activity or
work package: smaller activities increase both cost and accuracy of the
estimating process. The project management team must weigh the additional
accuracy against the additional cost.
.4 Computerized
tools. Computerized tools, such as project
management software spreadsheets and simulation/statistical tools, are widely
used to assist with cost estimating. Such products can simplify the use of the
tools described earlier and thereby facilitate rapid consideration of many
costing alternatives.
.5 Other cost
estimating methods. For example, vendor bid analysis.
7.2.3 Outputs from Cost Estimating
.1 Cost estimates. Cost estimates are quantitative assessments of the likely costs
of the resources required to complete project activities. They may be presented
in summary or in detail.
Costs must be estimated for all
resources that will be charged to the project. This includes, but is not
limited to, labor, materials, supplies, and special categories such as an
inflation allowance or cost reserve.
Cost estimates are generally expressed
in units of currency (dollars, euros, yen, etc.) to facilitate comparisons both
within and across projects. In some cases, the estimator may use units of
measure to estimate cost, such as staff hours or staff days, along with their
cost estimates to facilitate appropriate management control. Cost estimating
generally includes considering appropriate risk response planning, such as
contingency plans.
Cost estimates may benefit
from being refined during the course of the project to reflect the additional
detail available. In some application areas, there are guidelines for when such
refinements should be made and what degree of accuracy is expected. For
example, The Association for the Advancement of Cost Engineering (AACE)
International has identified a progression of five types of estimates of
construction costs during engineering: order of magnitude, conceptual,
preliminary, definitive, and control.
.2
Supporting detail. Supporting detail for
the cost estimates should include:
·
A
description of the scope of work estimated. This is often provided by a
reference to the WBS.
·
Documentation
of the basis for the estimate; i.e., how it was developed.
·
Documentation
of any assumptions made.
·
An
indication of the range of possible results; for example, $10,000 ± $1,000
to indicate that the item is expected to cost between
$9,000 and $11,000. The amount and type of additional details vary by
application area. Retaining even rough notes may prove valuable by providing a
better understanding of how the estimate was developed.
.3
Cost management plan. The
cost management plan describes how cost variances will be managed (e.g.,
different responses to major problems than to minor ones). A cost management
plan may be formal or informal, highly detailed or broadly framed, based on the
needs of the project stakeholders. It is a subsidiary element of the project
plan (discussed in Section 4.1.3.1).
7.3 COST BUDGETING
Cost budgeting involves allocating the overall cost
estimates to individual activities or work packages to establish a cost
baseline for measuring project performance. Reality may dictate that estimates
are done after budgetary approval is provided, but estimates should be done
prior to budget request wherever possible.
7.3.1 Inputs to Cost Budgeting
.1 Cost estimates. Cost estimates are described in Section 7.2.3.1.
.2 Work breakdown
structure. The WBS (described in Section
5.3.3.1) identifies the project elements to which costs will be allocated.
.3 Project
schedule. The project schedule (described in
Section 6.4.3.1) includes planned start and expected finish dates for the
project components to which costs will be allocated. This information is needed
to assign costs to the time period when the cost will be incurred.
.4 Risk
management plan. The risk management plan is
discussed in Section 11.1.3. In addition to this, the risk management plan
often includes cost contingency, which can be determined on the basis of the
expected accuracy of the estimate.
7.3.2 Tools and Techniques for Cost Budgeting
.1 Cost budgeting tools and techniques. The tools and techniques described in Section 7.2.2 for
developing project cost estimates are used to develop budgets for activities or
work packages as well.
7.3.3 Outputs from Cost Budgeting
.1 Cost baseline.
The cost baseline is a time-phased budget that will be used to measure and
monitor cost performance on the project. It is developed by summing estimated
costs by period and is usually displayed in the form of an S-curve, as
illustrated in Figure 7-2.
Many projects, especially larger ones, may have multiple cost
baselines to measure different aspects of cost performance. For example, a
spending plan or cash-flow forecast is a cost baseline for measuring
disbursements.
7.4 COST CONTROL
Cost control is concerned with a) influencing the factors that
create changes to the cost baseline to ensure that changes are agreed upon, b)
determining that the cost baseline has changed, and c) managing the actual
changes when and as they occur. Cost control includes:
·
Monitoring cost performance to detect and understand
variances from plan.
·
Ensuring that all appropriate changes are recorded
accurately in the cost baseline.
·
Preventing incorrect, inappropriate, or unauthorized
changes from being included in the cost baseline.
·
Informing appropriate stakeholders of authorized
changes.
·
Acting to bring expected costs within acceptable
limits.
Cost
control includes searching out the “whys” of both positive and negative variances.
It must be thoroughly integrated with the other control processes (scope change
control, schedule control, quality control, and others, as discussed in Section
4.3). For example, inappropriate responses to cost variances can cause quality
or schedule problems, or produce an unacceptable level of risk later in the project.
7.4.1 Inputs to Cost Control
.1 Cost baseline. The cost baseline is described in Section 7.3.3.1.
.2 Performance
reports. Performance reports (discussed in
Section 10.3.3.1) provide information on project scope and cost performance,
such as which budgets have been met and which have not. Performance reports may
also alert the project team to issues that may cause problems in the future.
.3 Change
requests. Change requests may occur in many
forms—oral or written, direct or indirect, externally or internally initiated,
and legally mandated optional. Changes may require increasing the budget or may
allow decreasing it.
.4 Cost
management plan. The cost management plan is
described in Section 7.2.3.3.
7.4.2 Tools and Techniques for Cost Control
.1 Cost change
control system. A cost change control system defines
the procedures by which the cost baseline may be changed. It includes the
paperwork, tracking systems, and approval levels necessary for authorizing
changes. The cost change control system should be integrated with the
integrated change control system, discussed in Section 4.3.
.2 Performance
measurement. Performance measurement techniques,
described in Section 10.3.2, help to assess the magnitude of any variations
that do occur. Earned Value Management (EVM), described in Sections 7.4.2.3 and
10.3.2.4, is especially useful for cost control. An important part of cost
control is to determine what is causing the variance and to decide if the
variance requires corrective action.
.3
Earned value management (EVM). All
EVM Control Account Plans (CAPs) must continuously measure project performance
by relating three independent variables: 1) The Planned Value, the physical
work scheduled to be performed, including the estimated value of this work
(previously called the Budgeted Costs for Work Scheduled [BCWS]), as compared
against the 2) The Earned Value, physical work actually accomplished, including
the estimated value of this work (previously called the Budgeted Costs for Work
Performed [BCWP]), and to the 3) Actual Costs incurred to accomplish the Earned
Value. The relationship of 2) Earned Value less 1) Planned Value constitutes
the Schedule Variance (SV). The relationship of 2) Earned Value less 3) Actual
Costs constitutes the Cost Variance (CV) for the project. See also Section
10.3.2.4.
.4
Additional planning. Few projects run exactly
according to plan. Prospective changes may require new or revised cost
estimates or analysis of alternative approaches.
.5
Computerized tools. Computerized tools, such
as project management software and spreadsheets, are often used to track
planned costs versus actual costs, and to forecast the effects of cost changes.
7.4.3 Outputs from Cost Control
.1
Revised cost estimates.
Revised cost estimates are modifications to the cost information used to manage
the project. Appropriate stakeholders must be notified as needed. Revised cost
estimates may or may not require adjustments to other aspects of the project
plan.
.2
Budget updates. Budget updates are a
special category of revised cost estimates. Budget updates are changes to an
approved cost baseline. These numbers are generally revised only in response to
scope changes. In some cases, cost variances may be so severe that rebaselining
is needed to provide a realistic measure of performance.
.3
Corrective action. Corrective action is
anything done to bring expected future project performance in line with the
project plan.
.4
Estimate at completion. An
Estimate at Completion (EAC) is a forecast of most likely total project costs
based on project performance and risk quantification, described in Section
11.4.3. The most common forecasting techniques are some variation of:
·
EAC =
Actuals to date plus a new estimate for all remaining work. This approach is
most often used when past performance shows that the original estimating
assumptions were fundamentally flawed, or that they are no longer relevant to a
change in conditions. Formula: EAC = AC + ETC.
·
EAC =
Actuals to date plus remaining budget (BAC – EV). This approach is most often
used when current variances are seen as atypical and the project management
team expectations are that similar variances will not occur in the future.
Formula: EAC = AC + BAC – EV.
·
EAC =
Actuals to date plus the remaining project budget (BAC – EV) modified by a
performance factor, often the cumulative cost performance index (CPI). This
approach is most often used when current variances are seen as typical of
future variances. Formula: EAC = (AC + (BAC – EV)/CPI)—this CPI is the cumulative
CPI.
Each of these approaches may be the correct approach for any given
project and will provide the project management team with a signal if the EAC
forecasts go beyond acceptable tolerances.
.5 Project
closeout. Processes and procedures should be
developed for the closing or canceling of projects. For example, the Statement
of Position (SOP 98-1 issued by the American Institute of Certified Public
Accountants—AICPA) requires that all the costs for a failed information
technology project be written off in the quarter that the project is canceled.
.6 Lessons
learned. The causes of variances, the
reasoning behind the corrective action chosen, and other types of lessons
learned from cost control should be documented so that they become part of the
historical database for both this project and other projects of the performing
organization (see Section 4.3.3.3).Source = A Guide to the Project Management Body of Knowledge (PMBOK Guide) by Project Management Institute, Newton Square, Pennsylvania USA 2000