How Cobra Calculates Forecast Scale EAC

Cobra runs the Calculate Forecast process using scaling methods such Hours, Currency, and Hours and Currency.

The Calculate Forecast Scale Retain EAC method works as follows:

  • Cobra scales the reporting set EAC. Forecast classes must be included in the Forecast class list and should be at the same control account or work package level. If not, Cobra encounters an error. Actuals classes must be included in the Actuals class list. If the Include in Actuals option (set on the General tab of the Project Properties dialog box) for the actual class is not selected, the class is also stored in the non-Actuals class list.
    • If the Scale Retain EAC option is set to Hours or Hours and Currency: Cobra gets a list of results with the sort code H results, a list of control accounts and work packages with at least one non-Hours base result in the forecast, and EAC, EAC Hours, ACWP, ACWP Hours, Sum of Cost results as ETC and Sum of Hours Results as ETC Hours.
    • If the Scale Retain EAC option is set to Currency: Cobra gets the EAC, ACWP (actual cost), and Sum of Cost results as ETC. If there are no sort code H results, the calculations will be Currency only.
    • If Scale Retain EAC option is set to Hours and Currency: Cobra gets the EAC non-labor and cost result Sum as ETC non-labor, where the sort code is not H and the time-phased classes are forecast classes in the EAC cost reporting set. Cobra also gets the ACWP (actual cost) non-labor, which is the sum of the cost results, where time-phased classes are in the actuals classes included in the EAC reporting set and sort code is not H.
  • Cobra scans all of the control account and work packages that are being calculated.
    • If the Scale Retain EAC option is set Hours and the control account or work package has base results of hour, or if the Scale Retain EAC option is set to Hours and Currency, and the EAC hours is greater than 0, Cobra performs the following:
      • Cobra calculates the Total Actuals Hours as Sum Actuals Hours + Non ACWP Hours.
      • Cobra determines the scale factor. If the difference between the (ETC Hours + Total Actuals Hours) and the EAC Hours is greater than 0.5, Cobra sets the Scale Factor to (EAC Hours - Actual Hours) / ETC Hours (If ETC Hours is not 0 and Actual Hours is less than EAC Hours). If the Scale Retain EAC option is set to Hours, Cobra scales resources based on the Scale Factor, all results, and all EAC forecast classes.
      • If there are no Hours base results for a control account or a work package, Cobra scales resources using Currency.
      • If there are no Hours and Currency base results for a control account or a work package, Cobra scales resources using Hours.
    • If the Scale Retain EAC option is set to Hours and Currency, Cobra performs the following:
      • Cobra scale the Hours Resources based on the scale factor, all results, all EAC forecast classes and sort code H results.
      • Cobra determines the Currency scale. If the difference between the (ETC Non Labor + Actuals Non labor) and the EAC Non Labor is greater than 1.0, Cobra sets the scale factor to (EAC Non Labor - Actual Non Labor) / ETC Non Labor (If ETC Non Labor is not 0 and Actual Non Labor is less than EAC Non Labor). Cobra scales the Resources based on the scale factor, all results, all EAC forecast classes, and results of Resources that do not have a sort code of H.
    • If the Scale Retain EAC option is set to Currency, Cobra determines the Currency scale. If the difference between the (ETC + Acuals) and the EAC is greater than 1.0, Cobra sets the scale factor to (EAC - Actual) / ETC (If ETC is not 0 and Actual is less than EAC). Cobra scales the Resources based on the scale factor, all results and all the EAC Forecast classes.
  • If the new actual costs are greater than the EAC, Cobra sets the EAC to match the Actuals for Currency or Hours and Currency. If the Actual Hours are greater than the EAC Hours, Hours, Cobra will set the EAC Hours to the Actual Hours if scaling Hours or Hours and Currency.

Scale Calculated Resource Values

Cobra scales the calculated resource values from the base result as follows:

  • Cobra gets the list of results for the resource assignments that match an EAC forecast class. If required, this is filtered by the sort code filter passed.
  • For each of the resource assignments, Cobra determines the current base result and the new base result, which is calculated as the base result multiplied by the scale factor.
  • Each result is then multiplied by the scale factor and the time-phased records are updated.
  • The EAC value associated with the resource assignment is then updated to match the current EAC minus the old EAC plus the new EAC.

Sample Calculations

This section illustrates how Cobra calculates Forecast Scale EAC.

We will use the information from this work package for each of the example calculations below.

Status Date: 31 Dec 15

Work Package Baseline Start Date Baseline Finish Date EAC Hours EAC
1.1.1.1\1110\01 30-Oct-15 31-May-16 $18,699.59 1000
Resource Class Total Spread
DRAFT Actuals 50 50
DRAFT Budget 1000
DRAFT Forecast

Hours Calculation

Advance the calendar to 31-JAN-2016 and set Actual start date to 30-OCT-2015

Resource Class Total Spread
DRAFT Actuals 100 50, 50

Calculate Forecast Scale: Hours

EAC $18,613.02
Hours EAC 1000
Resource Class Total Spread
DRAFT Forecast 900 225, 225, 225, 225

Currency Calculation

Advance the calendar to 31-JAN-2016 and set Actual start date to 30-OCT-2015

Resource Class Total Spread
DRAFT Actuals 100 50, 50

Calculate Forecast Scale: Currency

EAC $18,699.59
Hours EAC 1004.63
Resource Class Total Spread
DRAFT Forecast 904.63 226.16, 226.16, 226.16, 226.16

Hours and Currency Calculation

During this calculation, the Hour results are scaled to match the “Hours EAC” and the Non-Hour results are scaled to the “Non Labor EAC”. In this example, the TRVL has a Direct base result with a total for $500, however, the Non Labor EAC total is $2000. Since the Actual costs were increased by $50 to $550, the total for TRVL changes from $500 to $2000 - $550 = $1450.

Work Package Baseline Start Date Baseline Finish Date Status Date Non Labor EAC Hours EAC
1.1.1.1 \ 1110 \ 01 30-Oct-15 31-May-16 31-Dec 2015 $2000 1000
Resource Class Total Spread
DRAFT Actuals 50 50
DRAFT Budget 1000
DRAFT Forecast 1000 200, 200, 200, 200, 200
TRVL Actuals $500 $500
TRVL Budget $2000
TRVL Forecast 500 100, 100, 100, 100, 100

Advance the calendar to 31-JAN-2016 and set Actual start date to 30-OCT-2015

Resource Class Total Status Date
Draft Actuals 100 50, 50
TRVL Actuals $550 $500, $50

Calculate Forecast scale: Hours and Currency

Non Labor EAC $2000
Hours EAC 1000
Resource Class Total Spread
Draft Forecast 900 225.00, 225.00, 225.00, 225.00
TRVL Forecast $1450 362.50, 362.50, 362.50, 362.50