The Official Site for Zümmer – CPM Schedule Analysis & Comparison – Page 6 – Copyright ©2012-2026 FoxQuest Systems, Inc.

The Benefits of Zümmer

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.

Resolving Partial Date, Duration, Float and Lag 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.

Trap: “Must Finish By” constraint at 00H: 00M

If in the User Preference window, the Dates-> Time option is set to “Do not show time”, then P6’s schedule calculation of Total Float values could be incorrectly calculated when a date is entered in the Project –> Schedule Date –> Must Finish By textbox.

When time is not shown and a date is entered in the Must Finish by textbox, the time stored by default is: 00H: 00M. This means that the date shown will not be considered during P6’s schedule calculations during the backward pass. This oversight causes every Total Float value to be 1 day less than the correct Total Float value.

In the illustration below, the “Analysis Charts 1 of 2” reports 4 activities with negative float even though the “Must Finish By” date matches the Contract Completion Milestone in the schedule.

Zümmer’s Analysis Charts, Analysis Statistics and Project Settings reports provide the red alert message “Possible Bad Planned End Date – Check Planned End Date Hours” under the Planned End box when the “Must Finish By” constraint date contains “00H: 00M” as the time value.

When this situation occurs, first return to the User Preferences window then change the Time option setting to either “12 Hour (1:30 PM)” or “24 Hour (13:30)”.

Second, return to the Projects-> Dates option. the “Must Finish By” option will now show with the Hours, Minutes as “00:00”.

Then change the hours and minutes setting to reflect the ending hour and minutes settings for the Project (typically 17:00/5:00 PM or 16:00/4:00 PM) as shown below.

Lastly, recalculate the Project as normal. The resulting Total Float values will now correctly include the Finish date during the backward pass process.

Determining Added or Deleted “Driving Path” Activities

Regardless of the settings for Project->Define Critical Activities:

(a) Total Float less than or equal to; or

(b) Longest Path,

…after a schedule calculation, P6 will mark certain activities on the ‘Driving Path’. The term ‘Driving Path’ is not defined in P6, however, upon observation of the internal database table “Task”, the field name “Driving_Path_Flag” is set to “Y” for activities that are on the longest overall path as shown below.

Changes to the Driving Path between Project updates are possible, however, in P6, those changes are difficult to determine without first assigning a Project as a baseline.

In the illustration below, The Original Duration for Activity “LH930 – Paint Building Interior” was increased from 30 to 35 days causing the activity to fall on the Driving Path. Consequently, 3 activities were removed from the Driving Path.

Zümmer reports these changes in Comparison Reports #22/23 – Added/Deleted Driving Path Activities. Shown Below:

Comparison Report #22 – Added Driving Path Activities

Comparison Report #23 – Deleted Driving Path Activities

Analysis Statistics (1 of 2) – Information at your fingertips.

Zümmer’s, Analysis Statistics Report is the next level of detail from the Analysis Charts. The first of two reports neatly displays 6 key Project elements on 1 page. This matrix type report is ideal for Schedule Manager reporting. The illustration below is a sample of a typical Analysis Statistics Report.

1) Activity Status: Details the Status of every activity categorized by Activity Type.

2) Criticality: Details the Criticality State of every remaining activity categorized by Activity Type.

3) Constraints: Counts every Primary & Secondary Constraint and groups by Constraint Type.

4) Relationships: Categorizes all relationships based on Type. The R/A Factor (# of Relationships/# of Activities), measures the complexity of the CPM network, the higher the number, the more complex the CPM network. The L/A Factor (# of Lags/ # of Activities), measures the use of lags in the CPM Network. The higher the number, the more lag usage in the CPM Network.

5) Calendar: Lists all the Calendars used on the Project with individual Type, Hrs/Period, Totals and % Usage.

6) Additional Project Specifications and the Criticality Threshold values are clearly listed.

Reporting Activity Relationships with Laaaaag

Using lags in a CPM network is widely discouraged and is considered not “best practice” in the CPM community. In fact, using lags is probably the leading cause of faulty CPM networks. In Zümmer, there are actually 12 Analysis Reports (see illustration above) that deal with identifying various issues related to the use of lags.

Finding all the Relationship lag in a Primavera P6 CPM network can be a very time consuming effort. Unfortunately, there is no filter specification that can directly list all lags in the CPM network without first creating a P6 Report. After all that work, the output is not very appealing, not easy to understand and not ready for prime-time distribution.

In this article, we examine Report #28 – “Activity Relationships with Lags”. This report is the most general of the lag related Analysis Reports. The other remaining 11 reports, which will be covered in other articles, isolate specific anomalies resulting from using lags in an unconventional manner.

In the sample report output below, each relationship containing a lag value is clearly and individually paired. In addition, the Activity Status of the predecessor and successor is listed along with each Original Duration, the type of Relationship and lag value between the two activities.

Tracking & Reporting Logic Changes

Tracking logic changes can be a nightmare, especially when it comes to large CPM networks with ever changing scope and conditions. Many schedule specifications require that for each logic change, a description for the basis of each change is provided and specifically identifying the affected activities by Activity ID. In other words, the Owner is not just interested in what changed, but more so, why the change was made. Making matters worse, typically each change requires an individual explanation.

Zümmer provides you with seven (7) Comparison Reports designed to neatly account for every logic change between Project Updates.

1&2) Comparison Reports #06/07 – Added/Deleted Logic – These reports list and total the added/deleted logic changes between the Control and Modified Project ID. The reports sort by Predecessor Activity ID.

3) Comparison Report #10 – Added/Deleted Predecessors by Activity ID – groups predecessor logic changes by Activity ID. The action taken, Added or Deleted Predecessor, is coded as AP or DP. The total count is the sum of Reports #06 and #07.

4) Comparison Report – Added/Deleted Successors by Activity ID – is the same as Comparison Report #10 except the action taken, Added or Deleted Successors, is coded as AS or DS. The total count is the same as in Report #10.

5) Comparison Report – Changed Logic By Activity ID – (Illustrated Below) combines the Added/Deleted Successors report with the Added/Deleted Predecessors report. Since every logic change affects activities in pairs (the predecessor and the successor), this report provides an excellent reference document identifying each activity and all the logic changes affecting it.

6&7) Comparison Report – Changed Logic that Increases/Reduces Total Float – Are subsets of Item #5 above.

The Change Logic by Activity ID reports also displays, added/deleted activities, status indicators, and Total Float values.

How to: Audit Global Activity Code Usage

For those of you who routinely receive and/or submit P6 schedules, chances are you will eventually wind up with more Global Activity Codes that you can account for.

This is due to importing/exporting P6 schedules that are assigned to Global Activity Codes. If the Global Activity Code does not exist in your database, P6 creates a new Global Activity Code with the same name. Over time, your list of Global Activity Codes can grow to an unmanageable amount. For this reason, many project specifications prohibit schedule submittals containing Global Activity Codes.

In P6, it is exceedingly difficult to determine which Global Activity Codes are used by which Projects. In Zümmer, there is a much more efficient way to determine Global Activity Code usage. From the “Other Reports” menu, select “Global Activity Code Usage by Code/Project”, then either Preview or Print (See illustration below).

To eliminate Global Activity Code usage, open the Projects listed, and then reassign the Global Activity Code to a Project Activity Code. Later you can delete the Global Activity Codes you no longer need.

Not Started Activities with no Active Predecessors

If an uncompleted activity’s predecessors are all complete, then it would be reasonable to expect that the activity in question should be in progress. The possible exception is when a predecessor completes just prior to the Data Date allowing the successor activity status to be “not started”.

In any event, not started activities without active predecessors should be examined further to determine if the status should be updated or if a logic revision is required.

Zümmer Analysis Report #25 – “Not Started Activities with No Active Predecessors” lists all activities that:

a) have not started and;
b) the “immediate” predecessor(s) are all complete.

The column titled “ES Var To Data Date” lists the variance between the activity’s Early Start (ES) and the Data Date. If the variance is small or Zero, then this is typically an indication that the activity is “Riding the Data Date”; (meaning the Data Date is controlling the ES for the activity). If the variance is large, then this is typically an indication that the activity is restrained (commonly by the Retained Logic Rule) by an uncompleted “distant” predecessor.

Upon review of the schedule logic shown above and in the illustration below:

Line Item #1, Activity A1040, with and ES Variance =0, is “Riding the Data Date” and its immediate predecessor, A1020 – Activity B is complete.

Activity Relationships with Long Lag

In many Construction Project CPM Schedule specifications, the maximum Original Duration for “on-site activities” is limited to a certain value. A typical threshold limit is twenty (20) work-days.

When lags are used in a CPM network, the duration value used should be checked just like any activity. Since lags can be negative, then the absolute value of lags should be evaluated against the threshold limit for activities in the CPM network.

In Zümmer, the High Duration Threshold value set in the Criticality Duration Assignment window is used to determine if a lag falls in the “Long Lag” category. In the illustration above, the Duration Threshold High value is set to 20. The report identifies 5 relationships that exceed the threshold limit. Note for line item #5 below, the lag value is negative. In addition, the report defines the threshold criteria at the bottom of the page.