(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?
(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.
The purpose of project controls has been defined as: Project controls are the data gathering, management and analytical processes used to predict, understand and constructively influence the time and cost outcomes of a project or program through the communication of information in formats that assist effective governance and management decision making.
The question posed in this short post is how can we fulfil this objective when different processes calculate completely different for the same set of project data? The options for the calculated project delay for the simple project outlined above are:
- CPM using progress override calculates a 3 week delay.
- CPM using retained logic calculates a 4 week delay.
- WPM and ES calculate a 16 week (4 month) delay.
Which option is correct or are all of the options correct and project managers are free to choose the delay they prefer to report? Full details of the various options are outlined in Calculating Completion: https://mosaicprojects.com.au/PDF_Papers/P217_Calculating_Completion.pdf
My suggestion is a realistic prediction of completion needs more than a simple CPM update that assumes all future work will miraculously be completed as planned. WPM (Work Performance Management) has been developed to apply a similar approach to EVM, ES and ED, based on understanding the ratio between work performed and work planned and applying this factor to the future incomplete work to assess the likely completion date if nothing changes.
For more on WPM see: https://mosaicprojects.com.au/PMKI-SCH-041.php#WPM
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Thank you, Patrick. Not sure if I am much further forwards in my understanding.
From the early 90’s and through to about 2010, I did a lot of work with all of the wellheads and Christmas tree manufacturers. Most of them had sophisticated work management systems like SAP or some ancient software running on IBM GSD division kit like System 34/38, whose data quality was so poor that loading a planning system with the data did not provide the basis for EVM. Rather than fix the underlying data, usually a task of herculean politics impossible while trying to deliver a project, we took a fresh look at the ‘Value’ bit of EVM. Anything consistently measured for the ‘y’ axis seemed appropriate, and with a hugely complex, and priced, BoQ – we used sales invoice value.
‘When are we getting paid how much’ was a very popular question to answer with grey-hairs who maybe didn’t want to understand planning. Since then, I have often had to invent something for the ‘y’ axis to do EVM, and as long as the sum of the ‘y’ axis is equal to the worth of the project, no matter how that is calculated, we have an answer. Am I doing WPM with EVM?
I also see lots of big projects with no CPM data. Just checked and I am looking at a P6 project of a current client with 50k SAP workorders as activities and no logic. We can use P6’s EVM facilities perfectly well with this.
I enjoyed the paper you quoted. As a Scot, familiar with the work of Willliam Playfair, I am always amused at our American cousins’ proprietorial ‘Gantt Chart’ appellation. I did not find anything in the WPM definition and discussion I can’t do with P6. Admittedly earned schedule is a real pain in the ****, with Global changes and baselining way beyond the entry-level use that is normally made of it.
So, is the WPM methodology, a cute way to manage projects without installing terrifying PM software, just using the world’s most popular project controls software, Excel?
The difference between WPM and Earned Schedule (ES) is in the source of the 'metric' used in the calculations. ES relies on EVM data, and if the project is using EVM is the best option.
WPM uses a convenient metric that represents the work of the project. The only requirement is the metric is consistent across the work of the project, and preferably is already being used for other controls purposes. The original thinking was around concepts such as story points and function points in software projects using Agile, but system works with other options such as planned hours (and planned hours earned - not actuals), and an actual count of work produced, eg a project to upgrade 2000 computers simply needs to plan when the work shoud occur and then count the number actually upgraded.
WPM is intended as a pragmatic early warning system, rather than a scientifically precise contractual tool and can provide valuable insights working alongside CPM or other managment techniques see: https://mosaicprojects.com.au/PDF_Papers/P217_Calculating_Completion.pdf
Hmm. The very idea of a deterministic project finish date is unsound.
Quick question, (!?!), what is the difference between WPM and Earned Schedule?
Email: PPadmin@planningplanet.com
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