Finding Out-of-Sequence activities can be a time-consuming effort.
During the update process of a CPM Network it’s often likely to end up with Out-of-Sequence activities.
There are multiple causes for and multiple types of out-of-sequence conditions. The most common cause is when a successor activity is statused as started however the predecessor activity has not completed.
Especially in large CPM networks, with many activities statused during an update period, finding the root cause of an out-of-sequence condition can be a difficult task.
Consider for example, a situation, as shown below where an Activity “A” has not started and has only one predecessor, Activity “P1” that has completed. Typically, you would expect Activity “A” to start on the Data Date. However, as a result of scheduling using Retained Logic, Activity “A” is out-of-sequence by a number of days equaled to the remaining duration of activity “B”.
In this example below, tracing the logic back through 6 predecessors, Activities “P1” through “P6” finally arrives at the offender, Activity “B”. In this example, Activity “B” is the “not completed activity” while Activity “P6” is the “started successor”.
Finding out-of-sequence conditions using this technique and P6 alone can be a time consuming and frustrating effort. Especially if there are multiple logic paths that precede Activity “A”.
Zümmer Analysis Report #23 – “Not Complete Activities With Started Successor” list all activities that are Not Complete, and a successor is either In Progress or Completed.
In the illustration above, Line Item #1, Activity TD0012572, has not started and Activity 404-CM-1040, one of its successors, is complete. In Line Item #2, Activity TD0016440, has not started and a successor, Activity TD01010, is in progress.
The report sorts relationships by Predecessor/Successor Activity ID and the Predecessor/Successor Activity Name. The report then lists the Predecessor’s Early Finish, the Successors Actual Start, then continues with the Predecessor/Successor Original Duration, then the Relation Type and Lag value.
Other Zümmer Analysis Reports that fall in the “Out-Of-Sequence” category includes:
Analysis Report #24 – “Out-Of-Sequence In Progress Tasks”
Analysis Report #25 – “Not Started Activities with No Active Predecessors”
Years ago, while preparing a
schedule for what was then a 2-year project, I prepared a “5-Day Workweek – w/Holidays”
Project Calendar 1 year beyond the original completion date. At the time, I expected
a 1 year cushion would be more than enough to cover potential changes. However,
as the project progressed, changes accumulated and the completion date
eventually moved beyond the 1 year cushion I had originally created.
Unfortunately, I didn’t realize the error until an activity’s early finish date, set to a 5-Day Calendar with Holidays, coincidentally calculated to July 4. (oops!)
As a reminder, I now include the
expiration date as part of the Calendar Name.
In the illustration above, the Project Calendar Names above are now labeled as “5-Day Workweek – w/Holidays thru 2020” and “6-Day Workweek – w/Holidays thru 2020” . Since the 7-Day Calendar contains no holidays, an expiration date is not necessary.
OK, call me a “neat freak” but
after years of working with P5/P6, I eventually settled in on an EPS Structure
and Project naming convention that works for me. Of course, I’m sharing my
personal procedure, if you have other preferences, feel free to incorporate
them.
In the illustration above, the Top Node is the Project. I have other Nodes above such as Region/State and Company.
Below the Project Node, my subset
includes:
A
Node to contain the latest or “Current” Update. This Node usually contains only
1 Update.
A
Node for Previous Updates. For very long Projects, I occasionally include Nodes
grouped by Year so that there is no more than 12 Updates in each Node.
A
Node for the Baseline Project Schedule. If there are multiple Baseline Project
Schedules, I’ll create a separate Baseline Node for previous Project Baselines.
When
necessary, I’ll include Project Node subsets for “What-if Studies”, “TIA’s”, “Sandbox”,
etc.
For Project ID’s and Project Name,
my naming convention is in the format: “PPP-BL#-UP## – Project Name – Update ##
– DD dd-Mon-yy” where:
PPP:
is a 2 or 3 character code that is unique to each Project.
BL#:
References the source Baseline Project. i.e., the Baseline Project that the
current Update was derived from. Unfortunately, the reality is that “re-baselines”
can occur especially on multi-year projects. In the example below, if a
re-baseline situation occurs, that schedule will be designated as “MST-BL2” all
future Updates will be prefixed by “MST-BL2-UP##.
UP##:
Represents the Update Number which increments by 1 from beginning to the end of
the Project. The Update Number ## does not reset.
The
Project Name references, the Project Name, Update Number and the Data Date (DD).
Note that Project Updates are NOT embedded as “Maintained Baselines”. When it’s necessary to perform baseline variance analysis, I’ll select the baselines from the Updates or Baselines node, then “assign” the appropriate schedules as “Project”, “Primary”, “Secondary” or “Tertiary”, then “Restore” when the variance analysis is complete.
“Behind the scenes” calendar changes can result in perplexing date changes (or lack thereof) between Project Updates.
Changing calendar settings is an easy (and sometimes underhanded) way to “block out” days in the calendar thereby changing schedule dates.
Zümmer’s Comparison Report #44 – Changed Calendar Settings – reports and detects these types of changes. It is possible for Global and/or Project Calendars to have the same Calendar Name yet have different calendar settings. Detecting this type of change is extremely difficult and time consuming using P6 alone.
The Change Calendar Settings report compares the 2 Project Calendar Settings and identifies any added and deleted Calendar assignments. In addition, the report lists the Calendar Name, Type of Calendar used (i.e. Project or Global), Hours per Day setting, and Count (# of activities using that Calendar).
Added Calendars have no Control Project ID Calendar Name match while deleted Calendars have no Modified Project Id Calendar match.
In the illustration below: Line Item #4 – A Global Calendar was assigned to 1 activity. Line Item #3 – The Calendar Name, Type and Hrs/Dy match exactly, however (indicated by the Asterisk) there was a change in the underlying Calendar Data set. In other words, for example, one or more days were changed from a Standard to Non-work day or visa-versa.
Changes to Calendar Data may also involve other settings. This report does not identify exactly what Calendar Data changed, however, knowing that there is a change is sufficient to warrant further investigation.
Since Zümmer is a “report intensive application”, printing using Adobe Acrobat is an excellent way to process all Zümmer reports. However, the default Printing Preferences may slow down the process especially when printing multiple reports.
Changing the settings as noted below will vastly improve your experience when using Zümmer.
The instructions below work for Adobe Acrobat 9 Standard Version and Microsoft Windows 10. The procedure may vary with other Versions.
1) Create a New Folder on your desktop named Adobe PDF Output. (Fig. 1)
2)
Click on the Windows Start button and select Devices and Printers.
3) Right-Click on the Printer Icon used for Adobe Acrobat.
(Fig. 2)
a. Set as the Default Printer. A green check-mark appears on the bottom-left corner of the Icon.
4) Right-Click again and select Printing Preferences: (Fig. 3)
a. Uncheck View Adobe PDF results.
b. Click on the “Browse…” button to change the
Adobe PDF Output Folder setting.
c. Select Adobe PDF Output the click OK. Then click OK in
the Adobe Acrobat PDF Printing Preferences window. (Fig. 4)
In Zümmer, when the Print command button is clicked, all the selected reports
will then be immediately routed to the folder “Adobe PDF Output”. Later, you
can view all the PDF files when the print job is complete. A typical Zümmer
output run will take just a few (2 or 3) minutes to process.
The smallest PDF files by file size are usually blank (about 5-6K indicating that there were no results for that report), therefore, they can be sorted and deleted all at one time.
The instructions above apply to your computer’s user setting. Therefore, this will affect all applications. If you don’t want our printer settings to change then disregard these instructions.
What to do when you have more Global Calendars than you realize.
For those of you who routinely
receive and/or submit P6 schedules, chances are you will eventually wind up
with more Global Calendars that you can account for.
This is due to
importing/exporting P6 schedules that are have assigned Global Calendars. If
the Global Calendar does not exist in your database, P6 creates a new Global
Calendar with the same name. Over time, your list of Global Calendars can grow
to an unmanageable amount. For this reason, many project specifications
prohibit schedule submittals containing Global Calendars.
In P6, you can determine which
Global Calendars are used by Projects by selecting Enterprise->Calendars;
highlight a Global Calendar, then clicking on the “Used-By…” command button.
This method although effective is exceeding time consuming since you’ll need to
examine each Global Calendar usage individually.
In Zümmer, there is a much more
efficient way to determine Global Calendar usage. From the “Other Reports”
menu, select “Global Calendar Usage by Project” or ,
“Global Calendar Usage by Calendar” then either Preview or Print (See
illustrations below).
To eliminate Global Calendar usage, open the Projects listed, and then reassign the Global Calendar to a Project Calendar. Later you can delete the Global Calendars you no longer need.
The Progress Data report is used
to identify those activities that have “Progressed” in the “Modified”
Project when compared to the “Control” Project. In Zümmer, activities
are said to have “Progressed” when any the following events occur:
1) An Actual Start is achieved; 2) An Actual Finish is achieved; 3) The Remaining duration of an ‘In Progress’ activity is reduced; 4) The Remaining duration of an ‘In Progress’ activity remains the same and the Percent Complete is increased.
It is important to note that other sources, experts, or
organizations may define “Progress” based on varying criteria, however, in
general, the above 4 conditions cover the vast share of events.
The Progress Data report does not include activities that
are considered “non-progressive” revisions. In general, these
include:
1) Added or Deleted Activities; 2) Changes to Original Duration without a reduction to Remaining Duration; 3) Increases to Remaining Durations; 4) Unchanged Remaining Duration without an increase to Percent Complete.
This report is particularly
useful in documenting the Progress Only activities when creating or
investigating “Half Step” schedule updates.
The Progress Data report combines the following Zümmer:
[15] In-Progress Tasks With Reduced Remaining Duration
[31] Actualization Report (except for added activities)
[33] Increased Percent Complete (where the Modified Remaining Duration is
equaled to or greater than the Control Remaining Duration).
In the illustration below, activities shown are considered
“Progressed” because:
Line Item #1: Activity’s remaining duration decreased.
Line Item #2: Activity has completed.
Line Item #3: Activity has started.
Line Item #4: Activity’s remaining duration has remained the same, yet the % Complete has increased.
Key bullet points to help you with your decision to use Zümmer.
Simplicity
in form and function
Learning to use Zümmer is easy.
There is no prerequisite for lengthy or expensive training sessions. Most users are generating Zümmer CPM Analysis & Comparison reports minutes after installation.
Simply identify the 1) “Control” Schedule and 2) the “Modified” Schedule and you’re ready to run an Analysis Series and/or a Comparison Series of reports. It’s that simple. Each Analysis/Comparison report is well defined and many are numbered to match a line item in an optional 2-Page Summary Report.
Streamlines
and standardizes technical review time.
Running a schedule analysis or schedule comparison is easy
and takes just a few minutes. The result is a series of professional grade
reports, graphics and optional 2-Page summary that provides a complete profile
of the CPM Schedule changes, status, quality and overall content. By performing
a consistent analysis/comparison on a regular basis, you can be sure that each
schedule update is of the highest quality keeping you and the project team
up-to-date with the best possible and most reliable schedule information
available.
Flexibility
in Series Analysis/Comparison Report Content.
You have complete control over the number of reports
generated with each Analysis or Comparison Series. There’s no need to run reams
of reports just to access the specific information you need. Once a selection
of reports is made, you can even run the same set of reports against other
Projects. Simply, return to the Project Selection Tab, reselect the “Control”
and/or “Modified” Project(s) then return to the Analysis or Comparison Tab,
click Print and you’re done.
Helps to maintain a high-quality CPM Schedule.
If you prepare and/or update CPM schedules you want to be sure that your product meets or exceeds the guidelines established in the Contract Specifications. If you are responsible for receiving and reviewing schedule updates you want to know exactly what changed and quickly determine if the schedule changes are reasonable. With 88 Analysis Reports and 70 Comparison Reports, Zümmer has you covered no matter which side of the Project table you’re on.
Protects
your credibility as a Professional.
Every Project Scheduler knows the feeling of the pressures associated with delivery deadlines. When it comes to schedule updates, the Scheduler is typically the last link in the update process. It is vital that the Scheduler prepare and deliver CPM schedule updates with the highest level of confidence that all activities and activity changes are checked prior to delivery. The Scheduler’s as well as the Corporate’s reputation is at stake every time a product changes hands. Why take chances? When the Scheduler complete a schedule update, an attached Zümmer schedule analysis and comparison report not only demonstrates a high-level professionalism, but also provides the reviewer with a level of confidence that the update was performed with the highest level of care and concern for accuracy.
Identifies
cost anomalies relative to activity status.
When it comes to large schedule networks that are resource loaded, it doesn’t take long before tasks and cost get out of whack. With Zümmer’s specially designed analysis reports, cost vs. schedule anomalies are quickly identified keeping your schedules and cost data always in sync.
Documents “Work Orders” and “Issues”.
Nearly every construction project has its share of Work Orders (or Change Orders) and Issues. Zümmer’s Work Order and Issues Modules are design to integrate with P6’s Global Activity Code feature to produce easy-to-read and well-organized reports ready for Upper Level Management’s use and review.
Graphs and Reports activity status across multiple updates.
Identifying and communicating trends is a vital component for keeping a Project on-track. Zümmer’s unique Activity History Module allows you to plot and/or tabulate the status of any activity across multiple schedule updates. With activity progress reporting capabilities, you can spot trends and provide Project Managers and Upper Level Management with the necessary tools to proactively respond and resolve milestone slippages. The Activity Progress Graph displays an easy-to-understand plot of data date vs. update date data points. The Activity History Report displays the Original and Remaining Duration, Start and Finish date, Total Float and Days to Complete for each Update of the selected Activity ID.
Provides clear and concise reports useful to Upper Level Management.
Most corporate executives depend on timely and valuable information in a format that’s concise and easy to understand. Every Zümmer report is neatly designed with just the right amount of information appropriate for the topic heading. Furthermore, each report layout is developed in a consistent manner allowing the reader to quickly familiarize themselves with the data format, layout and information across multiple Zümmer reports.
Use the Total Float Distribution Curve to evaluate the condition of a CPM Network.
Analyzing and understanding the
distribution of Total Float (TF) values in a CPM network can be a very
revealing and useful indicator. In general, CPM networks with a more “Stressed”
Distribution tend to be more sensitive to Project delays as compared to
networks with a more “Relaxed” Distribution.
Zümmer’s Float Distribution Curve analysis report provides a graphical chart that can help you quickly determine the condition of the CPM Network. The generated graph plots the Total Float Values along the X-Axis, while the Y-Axis plots a Percentile value indicating the percentage of Tasks that have the X-Axis Float Value or less.
In the illustration below, for the “Stressed” Distribution graph, the range of Total Float Values is from 0 to about 1,210 (along the X-Axis) for the 2,243 Tasks distributed. However, at the 50% Percentile point (along the Y-Axis); the Total Float Value is about 50. In other words, about half of all the Tasks (approximately 1,121 Tasks) in this Project have a Total Float Value of 50 or less.
Similarly, in the illustration below, for the “Relaxed” Distribution graph, the range of Total Float Values is from 0 to about 870 (along the X-Axis) for the 2,725 Tasks distributed. However, at the 50% Percentile point (along the Y-Axis); the Total Float Value is about 175. In other words, about half of all the Tasks (approximately 1,362 Tasks) in this Project have a Total Float Value of 175 or less.
In comparison, and all else being equal, Projects with “Stressed” distribution are more likely to experience delays as compared to Projects with “Relaxed” distribution.
Determining a “Rule-of-Thumb” is subject to debate, however, by observation, Float Distribution Curves that are steep on the left side and flat on the right side, generally fall in the “Stressed” category. Whereas, Float Distribution Curves that are smooth from beginning to end generally fall in the “Relaxed” category.
Very Stressed distributions could
be a cause for alarm since this may indicate a Project schedule that is “Claims
oriented”. In these cases, you may want to consider reviewing the Project’s
overall logic schema to determine where relationships can be removed or revised
thereby increasing overall Total Float values.
Very Relaxed distributions could also be a cause for alarm since this may indicate a Project schedule that is insufficiently developed. In these cases, you may want to consider reviewing the Project’s overall logic schema to determine where relationships can be added or revised thereby decreasing overall Total Float values.
When it comes to CPM scheduling in the construction industry, generally, the smallest unit of time is measured in Days. In fact, many construction specifications state this categorically. However, in P6, the Duration, Total Float, Free Float, Lag values, or date that is displayed on the screen may be different from what is actually stored in the P6 database.
For example, if an Original Duration of 40 Days is assigned to an activity with a 5-Day calendar set to 8 Hours per Day, the value stored in the OD field (named Target_drtn_hr_cnt) is 320.00. In other words, P6 stores duration values in hours. (See Activity E in the illustration below).
In the illustration below, Activity ID A1020 and A1060 both have an Original Duration of 25 Days. However:
A1020 was updated by assigning a Duration Percent Complete of 35%.
A1060 was updated by assigning a Remaining Duration of 16 days.
P6 calculates the Remaining Duration for A1020 as 25*(1-.35) or 16.25 Days. The .25 remainder (or 2 hours) is reflected in the finish date as 09-Jun-16 10:00 (10AM). Meanwhile, A1060 displays the same Remaining Duration as A1020; however the finish date is reflected as 08-Jun-16 at 17:00 (5PM). Furthermore, A1060 is not on the Critical Path even though the Total Float value is displayed as 0 (the Duration Format Decimal value for the Day Unit of Time is set to 0).
The Partial Day effect can even cascade throughout the CPM Network affecting Total Float and Free Float values.
Analysis Report #26 illustrated below displays activities with Partial Original Duration, Remaining Duration, Total Float or Free Float values. Notice that although A1040 and A1060 have non-Partial Original Duration and Remaining Duration values, their Total Float and Free Float values are indirectly affected by the Partial RD of A1020.
2. Analysis Report “Partial Original or Remaining Duration” is a subset of Report #26 with the same format and display parameters.
3. Analysis Report “In-Progress Tasks with Partial Remaining Duration” is also a subset or Report #26 with the same format and display parameters.
4. In the illustration below, Analysis Report #27 identifies activities with Partial Lags.
In all the Zümmer Analysis Reports referenced above, the duration values are formatted in Days to rounded the nearest tenth. This format can also be replicated in P6 by changing the User Preferences in the Time Units tab Duration Format Decimals settings to 1 as shown below.
In addition, in P6, the dates can be set to show time values by changing the User Preferences Dates Tab Time section to 24 hour or 12 hour as shown below.
After printing or previewing the Zümmer analysis reports, find the partial day activities and/or relationships and revise the duration values accordingly to the nearest whole day. Since Total Float values are cascading, it is suggested to start with activities sorted by Early Start.
