Microsoft Project effectively records task durations in hours and the value of the duration in days is calculated from a parameter entered in the Options form.

This article is an extract from the book Planning and Control Using Microsoft Project 2013, 2016 & 2019 by Paul E Harris and explains how the duration in days is calculated, click here to read the article.

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Changing Durations and Assignments in Microsoft Project – PM Training

ms project 2010 training manual - spiral editionDurations and Assignments Change as Resources are Assigned in MS Project

Microsoft Project has some complex user definable relationships that determine which parameters change when resources are added to tasks. For example these relationships may result in durations or hours per resource reducing as resources are added to tasks.

This section will explain how resource assignments calculate and make some suggestions on how to set up the software so the tasks calculate the way you expect.

Task Type – Fixed Duration, Fixed Units, Fixed Work

Users must understand the relationship between the following parameters:

– The task Duration,

– The Work (the number of hours required to complete a task), and

– The Units per Time Period (the rate of doing the work or number of people working on the task).

The relationship is:

Duration x Units per Time Period = Work

For example, a 2-day task at 8 hours per day has a Duration of 2 x 8 =16 hours. If 2 people are assigned to the task the Units per Time Period is 2.00 or 200% and the work is 16 x 2 = 32 hours.

There are three Default task type: options and the default is assigned in the Tools, Options…, Schedule tab. Each new task is set with this Task Type. It may be changed at any time for each task in the Task Type field which may be accessed in a number of places such as the Task Type column the Task form, Task Details form and the Task Information form.

The Default task type decides how this relationship operates when one parameter changes. They are:

Fixed Duration The Duration stays constant when either the Units per Time Period or Work are changed.

A change to the Duration changes the Work.

Fixed Units The Units per Time Period stay constant when either the Duration or Work is changed.

A change to the Units per Time Period changes the Duration.

Fixed Work The Work stays constant if either Duration or Units per Time Period are changed.

A change to the Work changes the Duration.

Therefore your estimate will not change when you change Duration or Units per Time Period.

Eastwood Harris Supplies Project Management Training Manuals, Project Management Training Presentations and Consulting on Primavera P6 and Microsoft Project 2010 across Australia.

Related Article

The Best Way to Create “Views” in Microsoft Project

99 Tips and traps for microsoft project - ebookThe Smart Way to Create Views in MS Project Software

A Single Gantt Chart View is made from a Gantt Screen and includes a Table, an optional Group and an optional Filter. A View also holds the Bar formatting and Print settings.

If your project requires multiple but similar Views, for example, headers and footers may need to contain the same print settings and bar formatting consistent, then the following process is recommended:

– Create the first View and make sure the Bar formatting and the Print settings are correct.

– The print preview Header, Footer and Legend should read all the text data from the File, Properties form. Thus a change to the header or footer text can be made in one place for all Views, the File, Properties form.

– Ensure that you have hidden all the bars that you do not want displayed in the Legend, by placing an “*” in front of the bar name in the Bars form.

– Create new Views by copying the first View only after it has been checked, double-checked, and checked again.

– Each new View should have a unique name. This name is also used for the Table, Group and Filter names associated with the View, so each view has its own unique Table, Filter and Group.

These uniquely named Tables, Groups and Filters should not be displayed in the menus to avoid their inadvertent application and corruption.

Eastwood Harris Supplies Project Management Training Manuals, Project Management Training Presentations and Consulting on Primavera P6 and Microsoft Project 2010 across Australia.