The answer to this question will depend on the particular purpose of the schedule.
Is the schedule schematic for presentation purposes, executive summary schedule,
look ahead schedule, complete detailed schedule, etc.
Additionally of course the number of activities to be represented on the schedule
will vary with the complexity of the project.
For example a fabricator's schedule to the Client for the manufacture of some pipe
spools could have say 50 activities only and still provide sufficient granularity
for the Client to have an adequate understanding and feel for the project's activities
and progress based on this schedule. On the other hand if the schedule was to be
for a large multi-train dual fuel generator system created by the manufacturer for
distribution to the Client for communicating the execution plan and progress, then
many more activities would be required say a minimum of 200 activities to show some
basic level of granularity.
The above examples are for schedules by the Fabricator/ Manufacturer for distribution
to the Client. However internal schedules clearly road-mapping the execution plan
could for both of these referenced cases could easily contain more activities (and
therefore more definition) by an order of magnitude.
Therefore, the question of how many activities should a schedule have does *not*
have any fixed answer. However as a rough rule of thumb, one could *consider as a
starting point* the following:
Schedules to senior management
- For presentation purposes: 25 to 50 activities.
- For high level discussions: 100 to 300 activities.
Schedules to Client
- Simple fabrication projects: 50 to 150 activities.
- More complex manufacturing projects: 200 to 400 activities.
- EPC projects: 250 to 500 activities.
Internal Company Schedules
- Simple fabrication projects: 200 to 500 activities.
- More complex manufacturing projects: 400 to 2,000 activities.
- EPC projects: 1,000 to 5,000 activities.
Conclusion and Notes
Ultimately, when considering the amount of detail to be provided in the schedule
(number of activities) one must think of the primary function of the schedule: that
is to communicate both the execution plan and its timeframe. Therefore the number
of activities in the schedule shall be according to the necessary amount of detail
needed to convey the pertinent information to the intended audience.
Also it's very important for any schedule containing more than a 100 activities to
have a summary milestone section in the schedule. This will help any incumbent party
to quickly read and understand the important dates in the schedule. Without this
the reader is left to repeatedly flip back and forth through the pages in an attempt
to form a picture of the critical dates. Schedule readability is of extreme importance,
since lack of readership by the incumbent parties effectively renders the schedule