Guild of Project Controls: Compendium | Roles | Assessment | Certifications | Membership

Tips on using this forum..

(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.

Project Progress S-curve Analysis

8 replies [Last post]
Ellie G
User offline. Last seen 2 weeks 4 days ago. Offline
Joined: 1 Mar 2013
Posts: 6
Groups: None

Hi All,

I am putting together a project S-curve analysis presentation for project managers and I am looking for a reliable source that can provide a comprehensive  scurve analysis practice, specifically Early and Late data S-curve with actual progress.

an analysis the indicate if the project is in a good standing or not, what is the likelihood of delay if actual curve falls very close to late curve, etc...

I highly appreciate it if anyone provides me a document, link, etc to this sort of project analysis for project managers.

Thanks in advance

 

 

Replies

Zoltan Palffy
User offline. Last seen 19 hours 26 min ago. Offline
Joined: 13 Jul 2009
Posts: 2963
Groups: None

Ok Rodel has the same approach as me use the early and late dates for the curve and then use and average.

You can also do as Rafael shows 

here is a link to a free schedule validator that based on the status of the project perdicts the likehood of completing on time. 

the basis is the DCMA 14 point schedule analysis with a few other factors in the mix. 

https://schedulevalidator.com/

Rafael Davila
User offline. Last seen 6 hours 43 min ago. Offline
Joined: 1 Mar 2004
Posts: 5057

Please be reminded that:

  • Among others, renewable resources, materials, financial and date constraints must be considered in scheduling for the schedules to be feasible.  
  • AACE International recognizes their methodology to identify the Critical Path only works for traditional CPM schedules with no constraints.
  • Longest Path also fails at resource leveled projects, it is ancient calculation developed at the time CPM theory did not considered resource leveling in its calculation, it is time to let it rest.

Rodel Marasigan
User offline. Last seen 1 hour 10 min ago. Offline
Joined: 25 Oct 2006
Posts: 1587

It’s usually done by average of early and late. Or you can run a range analysis using P80. You can also use the critical Path or longest path for median.

Rodel Marasigan
User offline. Last seen 1 hour 10 min ago. Offline
Joined: 25 Oct 2006
Posts: 1587

.

Ellie G
User offline. Last seen 2 weeks 4 days ago. Offline
Joined: 1 Mar 2013
Posts: 6
Groups: None

Thanks, I appreciate it. 

my other question would be how should we define the median curve ? should it be 50-50 split of early and late unit or 60% or early and 40% of late unit?

Ellie G
User offline. Last seen 2 weeks 4 days ago. Offline
Joined: 1 Mar 2013
Posts: 6
Groups: None

Thanks Rafael Davila . Appreaciate it

Rafael Davila
User offline. Last seen 6 hours 43 min ago. Offline
Joined: 1 Mar 2004
Posts: 5057

There is much misconception about the use and interpretation of the S-curves. I find the AACE International Recommended Practice No. 55R-09 is an incomplete document regarding S-Curve Analysis.  Among other issues, the AACE RP does not mentions how under negative float P6 S-Curves are drawn and how are to be interpreted when late bars are projected earlier than early bars.

55r 09 Analysing s Curves - [Download PDF]

A complete set of S-Curves will not identify the critical path but will tell you if the job is on time or not, is limited on what it disclose.  For decades top management have been looking at these curves for a fast birds-eye view on actual status and projections.

When updating the schedule and the period of concentrated work is marked as 100% completed on an uncompleted activity with minimal remainig work the schedule and the S curves might be distorted unless the issue is properly addressed.  If there is minimal work remaining say 5% and the activity was marked 100% complete as to then the remaining 5% must still be scheduled while avoiding Out-Of-Sequence logic.

The Great Divorce: Cost Loaded Schedule Updating

devil8

Rafael Davila
User offline. Last seen 6 hours 43 min ago. Offline
Joined: 1 Mar 2004
Posts: 5057