Cost Rate, Cost, and Work not calculating correctly

[Conrad Santiago]

I am getting odd results among these fields on the same task:

Cost Rate; Cost; Work

For example on the same task (with a Fixed Cost of 0.00) with the same
resource I get these results:

Cost Rate = 100.00; Cost = 100.00; Work = 1 hr
Cost Rate = 99.80; Cost = 163.00; Work = 1.63 hr
Cost Rate = 100.41; Cost = 164.00; Work = 1.63 hr

In all of these examples, I am simply changing the Work value. In the last
example, I entered 1.64, but it won't display 1.64.

Why is this happening? Any help would be appreciated.

We are using Project Professional 2003 with SP2.

Thanks in advance for any responses.
Conrad Santiago

 

[Rod Gill]

I didn't think there was a Cost Rate field (there is a cost rate table with
possible values of 0 to 4). Can you hover your mouse over the column title
of cost rate and see what the underlying column is? It might be a custom
formula.

--

Rod Gill
Project MVP

Project VBA Book, for details visit:
http://www.projectvbabook.com

NEW!! Web based VBA training course delivered by me. For details visit:
http://projectservertraining.com/learning/index.aspx

 

[Conrad Santiago]

Rod,
Doh! You are right. I forgot I created that custom field. It's an
EnterpriseCost1 field with a formula of:

IIF([Work]=0,0,[Cost]/[Work]*60)

The Cost Rate Table values for the resource in the examples below are:

Effective Date = --
Standard Rate = 100.00/h
Overtime Rate = 100.00/h
Per Use Cost = 0.00

Cost accrual is set to Prorated.

The values are in the A table. The B, C, D, and E tables are not being used.

It seems when I enter a decimal of an hour for Work, the Cost value produces
odd, slightly off, results.

Also, I don't understand why, as in the third example, when I enter "1.64",
it displays "1.63.

In fact, after studying it more, it seems that when a decimal ends in
certain numbers it displays that number incorrectly. Specifically:

Enter Work = 1.01 and it displays Work = 1.02
Enter Work = 1.04 and it displays Work = 1.03
Enter Work = 1.06 and it displays Work = 1.07
Enter Work = 1.09 and it displays Work = 1.08

The last digit result is the same no matter what number you use. For
example, 1.01, 1.51, 25.31, 1004.01 will all display a Work value ending in
"2".

The good news is that the Cost value is correct in all of these entries,
however, my Cost Rate formula field is producing varying results.

Cost Rate = 99.34; Cost = 101.00; Work = 1.02 hr
Cost Rate = 99.56; Cost = 151.00; Work = 1.52 hr
Cost Rate = 99.97; Cost = 2531.00; Work = 25.32 hr
Cost Rate = 100.00; Cost = 100401.00; Work = 1004.02 hr

Any help is appreciated in understanding why this is happening. Thanks!
Conrad Santiago

 

[Conrad Santiago]

Well, I guess I'll answer my own question. With some more analysis, I
observed how MSP interprets hours. It takes whatever you enter as hours and
multiplies it by 60 to convert it into minutes. Then, it rounds it up to the
nearest minute.

To display the value back in hours, it divides that rounded number by 60 and
rounds the value to two decimal places.

This is why I can't enter a 10.01 and have it display 10.01. It displays
10.02.

Am I on the right track on solving this mystery?

Entry Entry*60 MSP RND MSP/60 MSP/60 RND
10.00 600.00 600 10 10.00
10.01 600.60 601 10.01666667 10.02
10.02 601.20 601 10.01666667 10.02
10.03 601.80 602 10.03333333 10.03
10.04 602.40 602 10.03333333 10.03
10.05 603.00 603 10.05 10.05
10.06 603.60 604 10.06666667 10.07
10.07 604.20 604 10.06666667 10.07
10.08 604.80 605 10.08333333 10.08
10.09 605.40 605 10.08333333 10.08
10.10 606.00 606 10.1 10.10

The next mystery to solve is why the "cost rate" changes when the units
change on a task. For example, if a task goes from 100% to 3%, the cost
changes. ???

Conrad Santiago

Rod,
Doh! You are right. I forgot I created that custom field. It's an
EnterpriseCost1 field with a formula of:

IIF([Work]=0,0,[Cost]/[Work]*60)

The Cost Rate Table values for the resource in the examples below are:

Effective Date = --
Standard Rate = 100.00/h
Overtime Rate = 100.00/h
Per Use Cost = 0.00

Cost accrual is set to Prorated.

The values are in the A table. The B, C, D, and E tables are not being used.

It seems when I enter a decimal of an hour for Work, the Cost value produces
odd, slightly off, results.

Also, I don't understand why, as in the third example, when I enter "1.64",
it displays "1.63.

In fact, after studying it more, it seems that when a decimal ends in
certain numbers it displays that number incorrectly. Specifically:

Enter Work = 1.01 and it displays Work = 1.02
Enter Work = 1.04 and it displays Work = 1.03
Enter Work = 1.06 and it displays Work = 1.07
Enter Work = 1.09 and it displays Work = 1.08

The last digit result is the same no matter what number you use. For
example, 1.01, 1.51, 25.31, 1004.01 will all display a Work value ending in
"2".

The good news is that the Cost value is correct in all of these entries,
however, my Cost Rate formula field is producing varying results.

Cost Rate = 99.34; Cost = 101.00; Work = 1.02 hr
Cost Rate = 99.56; Cost = 151.00; Work = 1.52 hr
Cost Rate = 99.97; Cost = 2531.00; Work = 25.32 hr
Cost Rate = 100.00; Cost = 100401.00; Work = 1004.02 hr

Any help is appreciated in understanding why this is happening. Thanks!
Conrad Santiago

I didn't think there was a Cost Rate field (there is a cost rate table with
possible values of 0 to 4). Can you hover your mouse over the column title
of cost rate and see what the underlying column is? It might be a custom
formula.

--

Rod Gill
Project MVP

Project VBA Book, for details visit:
http://www.projectvbabook.com

NEW!! Web based VBA training course delivered by me. For details visit:
http://projectservertraining.com/learning/index.aspx