There is no need to be in denial, it is not that difficult, just model one of the simple scenarios previously exposed and see it by yourself!  It is easier than resource leveling the beds on an oil rig [so simple] and never missing it.

There Are None So Blind As Those Who Will Not See

Vladimir,

90 per cent or more of the resources on any asset are supposed to be busy all the time. 

We need to aggregate operations, projects, maintenance to get a bed count. About 25-50000 activities depending on the size of the asset.  

I have a little slack time so I shall do some analysis on the metrics we use. 

I have started a wee project to investigate the legitimacy of saying that 100,000 manhours divided by a CPI equivalent of 7 productive hours a day = the number of men.

I have asked enough lead planners to project control managers to get data from over 500,000 maintenance work orders currently live in P6 across a dozen companies. 

I accept that just because we have done it this way for forty years does not mean that it is correct.

Personally, I think it is - but I have not done the maths. 

Zoltan,

I many times suggested an example when two resource units work with 50% workload (4 hours per day). Isn't it the same as one resource unit that works 8 hours per day if to judge only by manhours?

When we plan resources we want to know the number of resource units that shall be used on the project works at any time period. We need to know the number of beds, capacity of the temporal camps, how many machines shall be moved to the working site. “An average” is not sufficient.

An average makes sense only when all resources are busy all the time on the project works. In practice resource requirements are not exactly the same each day and month. It is necessary to know maximal requirements and try to smooth peaks if possible minimizing required resource quantities.

When resource requirements are different at some days of the month the number of required resources is larger than “average” in any case (even if to ignore part time assignments). That is why “average” is minimal resource requirements.

Project model is decision making tool. If it does not answer to questions like what if the number of available resources will be larger or smaller then it is useless for resource management and decision making. If the leveling never works for you look for more reliable software.

Zoltan, average does not mean that all resources are working full time during the time period. It looks more like minimal than average.

Resource assignment in hours do not show resource quantities. More than that, without taking into account required quantities resource leveling is not reliable and produces not realistic schedules.

The problem exists and it is more serious than just wrong reporting.

A schedule that does not meets any resource constraint is not feasible, in your case number of beds is one such limitation, perhaps not as interesting as the issue on production rates that must also be considered.  Well it seems like correct resource leveling of number of beds is an easy task.

very ineresting, Rafael, and I will have lots to say about your post later (I hope) - But some work has come in!  So I shall go and earn some money for a week......

Thank you David!

We have the same problem when import project information from the estimating software. For activity cost estimating manhours matter but the number of men does not. So we try to understand what resource crew shall be used on activity execution. It helps if there are leading machines. In this case we set activity duration equal to hours of the leading machine and calculate other resource quantities and workloads dividing their hours by hours of the leading machine. It is primitive but yes, if other information is not available there are no other options.

But when our team members know the technology or when we can get the answers from the specialists we create and assign real resource crews and use volumes of work and expected resource productivity for activity duration calculation. Resource hours is not initial but calculated data.

In corporate project management systems there are usually corporate reference-books (databases) that include resource productivity on different activity types, standard resource crews on different activity types, resource workloads on different activity types, etc. When such reference-book library is available then it is sufficient to enter activity type and volume and get everything else from the reference-books. Estimating data is used as the parallel estimate of the same work for comparison.

Fascinating discussion, I have been a way for a few days actually working which is a nice change given that I work in Oil and Gas which is a wee bit quiet at the moment.

Of course, everything Vladimir says about FTE not being translatable to number of actual men by dividing manhours by a constant is true, BUT:

I live in a world where the scope of work estimate is always in manhours. These are almost always what our American cousins call Wrench Time. No meal breaks, no permit delays, no walk-to-work.

Contractors have sophisticated Work Management Systems (WMS) that have norm based estimating systems within them that create a manhour content that is NOT FTE compliant, e.g. what does 47.45hrs of Pipefitter, and 17.32 hours of Rigging actually mean in terms of number of men on the job? I have never encountered an estimating system in my Oil, Nuclear, Defense, Ship Building, or Renewable worlds that tells me “how many men”.

For forty years what we have done next is to impose a methodology that helps us understand the impact of non productive time. We do not have “resource efficiency” or anything like it in P6 – so we either:

1. Reduce resource availability (e.g. I’ve got 6 electricians, so I will tell P6 I have 4)

2. Factor the manhours (e.g. this job is at the flare tip, needs three permits, a LONG climb to work – lets multiply the manhours by 3)

3. Reduce the number of working periods in the scheduling calendar. (e.g. We are paying for 12 hours, but on a satellite platform we only get 4 working hours per day.)

Option 3 is universal as it preserves the manhour content in the estimate which option 2 makes irreconcilable, and does not increase my FTE algebra as option 1 would.

So I am left with Wrench Time and an activity calendar that seeks to match CPI. Dividing one by the other to approximate FTE is the best we have got. Yes, we could ask the maintenance manager to code some FTE information on the 25,000 PMRs he has per asset, but he would probably just ask us to change our medication. The obsession with CPI in my wholly reimbursable world makes it the commercial divisor of choice.

There has been a breakthrough for the asset owners in the FTE debate. The asset owners I do most of my work for are the operators of offshore oil and gas installations. Having more men on the platform than there are beds (strictly speaking, seats in the emergency escape vessels) is illegal. The common logistics package which monitors all movements of personnel, helicopter flights, crew rotas only knows about number of men. We must have exactly a full complement of men on board at all times. Dividing P6’s manhours by anything is no way to meet the statutory obligations. The interface between P6 and the Vantage logistics system has been a tortuous path through exquisitely complex spreadsheets.

Let us take a worse case example from Vladimir’s complaint about FTE. We have to send a specialist offshore to do a job estimated at 4 manhours. We need a flight out and a flight back and a bed for all the time he is there. Only the logistics system knows the flight dates and hence the duration of the activity. The system at the early adopters allows someone using the P6 Window’s client to send a request for an offshore visit directly to the queue of the logistics system, and when successful it writes back the date of the fights in and out – and a new resource assignment “Bed” for every day the specialist is offshore to do the 4 hour job. If our specialist’s return flight is delayed, then the Actual FTE is more than the Budget FTE.

The bit I like most is when the crew swipe through the heli-deck with their ID cards, the Resource Availability in P6 is updated.

This means all of the really difficult FTE sums are done in the logistics system, and the results written to P6. P6 behaves perfectly well with this data – I would just HATE to have to type it into the Resource Assignment table myself. 

So P6 can work with manhours and the difficult relationship with number of men. It just needs some help with the maths. P6 is light on estimate-and-approval, and I put “The Valdimir problem” in that category.

Now whether this whole issue is for “scheduling” software to solve or the WMS is a rant for another time…….

in P6 we use FTE

• Then P6 users are doing wrong math.  What it is amazing is how some P6 users cannot see the trap even after it is called to their attention.

If you have assigned 16 man-hours of resource A in one month; sixteen divided by 172 yields 0.0930023 which is meaningless.

• It might be you need two resources A working together the same day for 8 hours or it might be you need just one resource A working two days for 8 hours each day. Or it might be you need four working as a team for four hours, in such case one single resource working for 16 hours will not make it as in order to do some work he needs the assistance of the other three.

If you have assigned one man-hour of resource A in one month; one divided by 172 yields 0.0058139 which is meaningless, if you divide it by 8 if looking at a dally distribution you will get 0.125 which is also meaningless.

• It might be you need four resources A working together the same day for 15 minutes.

P6 resource histrograms are not a reliable way to determine resource quantity needed!

While full-time equivalent employees (FTE) is used for some accounting purposes it shall never be used to determine quantity of resource requirements.

The flaw in P6 resource leveling not always surfaces out when resource leveling the schedule but it does without any warning as reported by others.

Zoltan, I do not recommend anything special because do not know P6 as good as you and David.

I expected to learn about some workaround but it looks like it does not exist and P6 resource planning and reporting are not reliable.

We do not have this problem because Spider Project plans and reports both resource quantities and resource work hours.

Zoltan, FTE is not an industry standard in my country. Fortunately we do not accept follies as industry standards.

And besides if something is totally wrong why to use it even if it is an "industry standard"?

Do you have other arguments except "this used ALL of the time"?

Vladimir,

I know about this issue but I do not have P6 license as to showcase it. I wonder if Microsoft Project is equally flawed. I also know about Asta PP resource leveling flaw that will allow resources working on a single activity to be assigned at different times when the usual requirement is to keep them working as a team.

The devil is in the details, you will not get rid of it by simply pretending there is no devil.

Best Regards,

Rafael

• FTE is just the man-hours per month divided by a constant, it does not provide any additional information other than man hours divided by a conversion factor. Take a look at the following schedule and tell me what is the use of FTE. All resources are working on same 8HD5DW calendar, it does not provides useful information as to determine how many resources are required.
• I have never worked on a single construction job where all resources are assigned the same 8HD5DW calendar but lets model such a schedule, for the sake of never say never. 
• 

working a standard 8 hour shift per day 5 days per week its still 172 this will give you the FTE

Simple example: activities 1, 2 and 3 require a worker with 60% workload (60% of the worker work time). So each of them require a separate worker. If these activities are scheduled to be executed in parallel then they require 1.8 manhours per hour but 3 men to do the job.

Another example: at the beginning of the month 10 people are assigned on project activities, then only 2 persons. Total manhours will not show peak resource requirements.

Below the project that illustrates what did I mean. Activities 1, 2 and 3 are linked with SS dependency with 10 days lag, each requires a worker with 60% workload.

At the bottom resource histograms that show quantities and manhours by months and by days.

You may notice that second month requires more manhours but less quantity.

I have read in the original post: “I am trying to display the histogram by Month with the number of men shown down the left hand side rather than the hours for the month.”

FTE does not show required resource quantities.

Planned number of men per month (week, day) is not based on manhours. Resources may be assigned part time, there my be idle times between activities where certain resources are used. Resource quantity per period may mean peak quantity and applying resource leveling these peaks may be smoothed.

It looks like P6 just does not plan and report resource quantities. It creates problems with P6 resource leveling reliability. I do not mean schedule optimization - with wrong quantities the resulting schedule may be not feasible and required resource quantities underestimated.

P6 does have a few issues with resource quantities that are really only obvious if you look at more sophisticated software.

For Example  "Resource Efficiency"  i.e. i pay for 12 hours, how much actual work do I get?  Has occupied some of my time every week for the last 40 years, and P6 really only has 20th century work arounds. You could argue that such work arounds while rather old are at least well tested. They are also quick to apply.  In its defense we have a limited time to guess what to do next. That we use deterministic tools in planning for what is essentially a probabalistic environment is perhaps the greatest of these compromises. We cannot say "stop the project, I have not finished planning it"

when it says to use an average for the manpower it uses what values that you have set in the users preference under the Time Units tab under hours per time period. It does not mater that some months there are 29 days or 30 or 31 days per month.

So if you look at how the 172 was derived which are the standard working hours per month based off of working 8 hours per day 5 days a week it is 172/40 or 4.3 weeks per month on an average. So take 65 * 4.3 = 279.5 working manhours per month. 

So when you do your graph per month instead of using the default average so like you did when you were looking at it weekly and over ride the setting and you typed in 65 just type in 279.5 to get average manhours per month and this will give you the number of men required by MONTH based on working 65 hours per week. 

Hmm, you can’t do what you want, and I am unclear why you would want it……

If I have four activities on a finish to start relationship, the first lasts exactly January, the second February, the third March and the fourth (imaginatively enough) all of April, I have four activities that are “One month” long and have three finite durations between them.

If I then add a resource to each of the activities, lets keep it simple one person working full time, I have three different budgeted units across the four activities.

The Calender I use for these “Task Dependent” activities has “Time Period” settings of 8 hours for the day, 40 hours for the week – and then I am stuck. What is the hourly translation of a “Month”. There is only one value held and four possible values ((28,29,30,31)*Hours per day). So you cannot see a “smooth” histogram if I aggregate by month and want to see average utilisation by month because my four monthly Budgets share three different values and only one divisor…….

BUT if I want to know “how many men I need this month” I can just use the “weekly” figures instead? If I aggregate the four months over the roughly 16 weeks, then all of my 16 sub-totals are divided by 40. This is the same number of men as a monthly sub-total divided by the correct amount (which I do not have access to)….

Unit of measure is a label for Material resources ( e.g. foot, m3, pair etc) it has no arithmetic impact. Just a lable.