What is the best method to use for determining the percentage completion for a project (man-hours or cost) ?
Some projects specially the industrial one the cost of procurement activities for the equipments are very high comparing to the cost of the construction activities, in the meantime, the man-hours of the procurement activities is very low comparing to the construction activities. When a share holder or an employer ask a question what is the overall percentage completion of the project
You may present the overall percentage completion of a project by one of the two scenarios:
But the problem that at some stages of the project The employer might make a comparison between what he have spent of the project budget and the overall percentage completion of the project and he will find out that he spent a considerable amount of the project budget but the project have not been progressed as expected.
2. Cost basis
If you use the cost basis to present the overall percentage there will be a big differences between the overall percentage on the documents and the actual status on site.
I solved this problem by presenting the two scenarios together and explaining the situation and why it look like that, but is there is a method that combine both together (man-hours and cost) or any other method.
I think you need to report on both metrics because they really are different, and much of the accuracy (or ability for the two metrics to align) is subject to how the costs are tracked. This flows over into the earned value system, and here are some comments about the use of cost loading and reports.
When updating the schedule, when using EVMS with cost loaded activities, I recomment that you disconnect Remaining Duration and Percent Complete so that time and cost are updated differently. There are a number of reasons for this:
• I have found that project personnel on site who provide update information (usually superintendents) are not particularly accurate at providing reasonable predictions of percent complete and when they provide those estimates, they are totally pulled out of the air (to be polite). But supers always know when an activity is going to be complete, so their estimates of remaining duration are generally very accurate.
• At least with Primavera, if you leave PC and RD linked, one will change the other, but the EV metrics for Cost and Earned Value will be identical, eliminating the ability to provide SPI and CPI as different metrics and you lose the ability to really track both time and cost separately, which is vital to the EVM system.
• Remaining time and percent complete very often do not really have much to do with each other, especially if costs were not segregated such as to pull large values out of time related durations. So if a light fixture package is worth $100,000 of the $200.000 value of the activity, and the “Install Light Fixtures” activity duration is 10 days, then the work is NOT earned at a rate of $20,000/day, but rather the package value of $100,000 is earned on the first day of installation (or before) and the earned value of the work is $10,000/day. So, the activity has earned 50% of the value on the first day, and the remaining 50% is earned over the next 10 days. And, many contractors do not separate out the delivered materials values (in fact, often Contracting Officers have heartburn over this better approach), so many EVM systems are faulty. This means that man-hours and percent complete are not closely correlated UNLESS the cost loading was done carefully by pulling out all the costs that are not proportional to the durations.
• If the RD and PC are left linked, and the Contractor is updating with RD, the CM on the project is likely going to either hold back invoices because they are overly aggressive (since they may earn more money than the RD shows), or require the Contractor to increase PC values such to improve the predictions of completion which will provide an overly optimistic prediction of completion.
Further to the Comments Made Above, this is a common scenario in most projects prior to reporting on Progress Achieved it is imperative to identify and agree on the reporting structure with the key project stakeholders,
Let the Client know in advance to assess the progress on both the parameters
1. Time Progress : Gives Actual % complete against plan % (Time)
2. Value of Work (VOWD) Progress : Gives Actual % Complete against plan % ( Value of Work)
3. Critical Path Analysis on Update : Gives the most important answer when the project is going to be complete, what is critical path on the update, what are near critical sections, issues needing focus and attention.
The Progress Performance need be looked at from these three parameters and should not be mixed.
Physical Progress Report - Based on either Resource Man-hours or easier way of time weightage pointers utilizing the Progress Update Feature provided by the System.
Benefit of Time Weightage pointers is especially for properly reporting in detail the pre-construction stage works alogwith the Construction Stage Works. The Disadvantage faced by Planners is that most of pre-construction works are not resource loaded.
As soon as the CPM is made, even before you do any detailed resource loading and get into man-hour calculations, the system allows you to see the Forecast % Completion Values per plan on the Time Spread for different phases : Prelim, Engineering, Procurement, Construction, testing commissioning and handover.
Say the plan curve generated will have % values
On 25% Time - 20% Progress Planned (Pure Time)
On 50% Time Spread - 45% Progress Planned
On 75% Time Spread - 70% Progress Planned
On 100% Time Spread - 100% Progress Planned
Same could be done at monthly intervals.
Plan Physical progress curve thus generated based on the pure time taken to get the works done across the time spread is then frozen , following which getting progress updates at much early stage even when resource mobilization, site and camp establishments are in progress is also possible within 5 mins. of making a progress run (taking into consideration that these activities are generally not resource loaded mhr loaded but need be depicted as progress).
Another example would be while procurement of long lead items - you would not necessarily assign manhours for period following manufacturing to delivery to site, the progress curve generated with time weightage pointers gives a true estimate of the works accomplished on pre-construction stage.
Well said Mr. Steven,
I am also updating my schedule without linkage of Unit % Complete and Remaining Durations, But to do this procedure i am using following method
First i enter remaining duration based on remaining quantities, in result of entring remaining duration unit % complete calculate automaticaly which often not realistic
To make it realistic, I used to put 0 % to Percent Complete column and then i enter actual % Complete based on completed quantities,
As i have loaded the resource of manhours, quantities and revenue to my schedule, So the actual units been updated, and based on same units, Manhours % and the Performance % calculated
So the one is Physical %
and the second is Finacial %
The reason why i have listed above my procedure of updating is to know that is it ok, and i also want to know that is there any other way to unlink the % Complete and Reamining duration
Last Edit: 4 years, 8 months ago by Rizwan. Reason: (NULL)