Hi all
Ive got a client who is about to replan for OTB. They are arguing internally about whether to set s=p or s=p=a. I'm of the opinion that they should do the latter so that CPI and SPI are reset to 1. There is no particular reason why they should maintain the cost variance in the replan.
I wonder if anyone knows of any official standards or studies to support the position that s=p=a is the way to proceed. The ANSI/EIA standards are painfully vague and there is plenty of anectodal reasons, but i'd love something formal to clarify the point.
Cheers
Hi, Andrew. Yes, that makes it much clearer – I now know exactly what I don’t understand! It’s the phrase “for the current work”. Does that mean the work scheduled to this point (BCWS), the work completed so far (BCWP), the ongoing work (i.e., work that is started but not finished), or the future work (not yet started)? Or all of them?
In general, I am opposed to re-baselining except for product scope changes. If more money/time is needed, we should just accept that and make it available – there really is no need to change the earned value baseline. However, team members often feel pressure when running late or going over budget, and this can lead to bad decisions – out-of-sequence work, scope and quality pruning, risky shortcuts, cheaper and less skilled resources, etc. To prevent that feeling of pressure, organizations will sometimes change the earned value baseline to reflect additional funding when it becomes clear from the CPI and SPI that costs and durations have been underestimated. However:
Andrew, I recently completed my new book Managing Projects as Investments: Earned Value to Business Value, due out from CRC Press in September. It has two chapters on earned value of which I’m quite proud. I think they explain the concepts in a simple and comprehendible manner, identify the shortcomings and easy ways to improve them, and illustrate some of the more sophisticated techniques. So I am going to kinda plagiarize from my own book and share a couple of concepts that might help you:
For your new baseline of the future work, I urge saving a separate BCWS for schedule (SV, SPI), distinct from the one for cost (CV, CPI). Even though traditional EVM pretends they aren’t, schedule and cost are different! Schedule is driven by the critical path, but the cost is critical path blind: a dollar is a dollar is a dollar, whether spent on an activity with 30 days of drag or 300 days of float. The critical path is THE most important aspect of schedule, so to ignore it in tracking schedule, as traditional EVM does, is hugely distorting: an activity with 300 days of float but a budget of $100,000 is worth 10 times as much to the SPI as one with 30 days of drag but a budget of only $10,000. This not only distorts the SPI, but leads to “gaming” the SPI by grabbing noncritical but big budget activities and even doing them out-of-sequence to the detriment of the critical path activities and ultimately to the project duration. This can be fixed by:
I hope this all helps, Andrew. I will now reference my book (from which I stole this last part!). If you think this info has been helpful, I’d certainly appreciate your consideration of a pre-order.
http://www.crcpress.com/product/isbn/9781482212709
Fraternally in project management,
Steve the Bajan
Ah sorry everyone. I've been speaking internal Earned Value Management colloquiallism for a few days, guess my brain is wired. Let me try again...
A project I'm looking at is running way over budget and schedule, ie Over Target Baseline (OTB), so they have decided to replan the rest of the project, and acquire further budget, in order to set a new more useful performance baseline. As normal for Earned Value Management rebaselining, they they need to reset the Schedule Performance Index to zero by setting BCWS equal to BCWP (S=P), for the current work. We are trying to convice them to also reset the Cost Performance Index by setting BCWS=BCWP=ACWP (S=P=A), but they are reluctant.
Pretty spefic EVM stuff, does that make it any more clearer?
Whew! Thanks, Mike! Thought it was just me...
Fraternally in project management,
Steve the Bajan
Hi Andrew
Welcome to Planning Planet
I would really like to help but I have no idea what you are talking about.
Best regards
Mike Testro