Percent complete calculation

There is an article on my website that may be of use to you under technical articles.

Paul E Harris
Eastwood Harris Pty Ltd, Melbourne, Australia
Planning and Scheduling Book Publishers, Training & Consulting
www.eh.com.au

Dear Paul,

Your website is really an impressive one. Lot of changes have been taken place when i compared with my last visit to your site and the site is neatly updated to match present requirements, Great! Also information is found to be useful one.

Excellent work.

Cheers!!!

Daya

Paul Harris
I too was impressed with the knowlegable information on your site. Recomend other to vist it.

Dear Paul:

Your info on percent complete is very thorough; However, I think the option I need is the only one missing.

Even when I feed Suretrak only durations (no resources, no costs), with each update, it computes percent complete for each activity, as well as summarized by code and for the project. How is it computed in this case?

Ernesto Puyana

If I recall correctly when no resourses are applied to a project then the summary % Complete is the based on 1 minus the sum of the Remaining Durations divided by Original Durations.

This is simple to test by creating a small schedule with predictable results and progress it.

Paul E Harris
Eastwood Harris Pty Ltd, Melbourne, Australia
Planning and Scheduling Book Publishers, Training & Consulting
www.eh.com.au

That makes sense, and explains why percent complete sometimes decreases from one week to the next, when activity finish date starts to creep.

Thanks a lot

Hi Paul,

Explain that one again please, especially pertaining to milestones???

Hi Paul:
I’ve experienced that problem in tracking building construction.
At the begining, everything works fine, since structure progress is usually straigth forward. But once the finishing activities set on, things begin to deviate: It´s not unusual to have multiple unfinished activities, which remain unfinished week after week; therefore, their early finish date creeps on an on, past their baseline finish date. If you divide remaining duration by an increasing total duration, you get a smaller percentage each passing week.

Of course it happens when operations are not running well, but have taken it as a good alarm point.

I haven´t seen its effect on milestones, but it affects summary activities, and groups of activities organized by codes.

Hi Ernesto,

This problem of activities not being completed can normally be attributed to two main factors, either extra works/modifications, or resources being mixed in activities ie the definition of the activities do not clearly specify where they end, the activities should be split up int punchlists, practical completions etc. It is simpler to add another activity rather than keeping one open for a small problem, at least you will understand what to focus on. If there is a problem, rather seperate it from the activity, and close of the activity concerned and people will understand what the problem is, rather than leave it festering, and nobody in management knows exactly where the problem lies.

Dear Philip,
I agree with you in totality regarding splitting the activity in terms of completed & non-completed ones.
Only then one can attack the real problem.
Cheers
DAttatreya

I also agree. It is very common that activities get to a 95% completion, and remain there for several weeks, awaiting some minor detail. In that case I apply a "substantial completion" criterium and consider it done. It’s up to residents to make contractors finish such details before full payment.

However, sometimes activities creep past their due date because of a bad estimate or a different constructive approach being applied, which delay a substantial percent of it´s scope. Splitting is a good solution there, but then, the new activity will not be in the baseline and will alter the planned percent complete curve.

If the activity is 95% complete & is waiting for some details (i.e if it is in a waiting perios), suspend the activity & resume the activity when it starts again.
But this is applicable only if the activity can be defined as a separate entity i.e unamigiously.
If the activity is such that the remaining work literaly crawls, then its a different issue.

Dear All

Unfinish activity - that is what I normally refer to the "80-20" rule

20% time and effort to finish 80% of the work
80% time and effort to finish 20% of the work

Comments??

Cheers

Alex

Dear Alex,
Broadly speaking, it is true in most of the cases.
I prefer the 70:20:10 rule or ABC or VED analysis in a management parlance.
I have personally experienced this phenomenon while working in an Engineering Consultancy org (Cost plus Contracts).
For e.g if u get paid 70 % for a AFC drawing approved in Code-2, 95% for approval in Code-1 & 100 % for as built drawings. the first 70 % is quite easily managable, it may take more than one revision to get it approved in Code-1 (another 20%), & As-built drawings: how many revisons????
This is reflected intoto in Manhours consumption profile.
Guess thats the reason why the progress is in the form of a S-curve.

Cheers
Dattatreya

I’m so glad this thread is getting interesting.

I can see now, my problem is not uncommon at all. But how about solutions? Is it also valid for you guys that only measures aimed directly at the contractor’s pocket produce results?

What if we setup a payment system tied up to this percent complete figure I’ve been talking about. Postponing the end of unfinished activities week after week would decrease the completion percentage, which would result in no payment that month.

Would that be feasible?

I think some of the discussion so far highlights the problem of extra work and punchlists, Here is a typical example of the process used on some projects I have been handling, this relates to piping activities post construction complete.

Pre-hydro punching - Contractor
Pre-hydro punching - Managing Contractor
Pre-hydro punching - Client
Hydro Test
Re-Instatement by contractor
Post-hydro punching - Contractor
Post-hydro punching - Managing Contractor
Pinting/insulation and Box up by contractor
Final punching - Managing Contractor
Final punching - Client

This sounds not to bad, but remember if any punch items are found during any of the Punching activities these items must be rectified. So if the quality on the job is not good, you can probably add another three activities. So if you have 800 testpacks, you could end up with anothe 8000 yo 10000 activities you have ignored, and these will bite you in the ass, if you do not watch out. This is why detail in planning is important.

Hope this makes some sense of the problem of activities not reaching completion.

Regards

Philip