Possible Sources of Errors

Because of the possibility that schedule status information has been entered directly into detail files without having undergone a validation process, errors can occur during earned value calculation.

Cobra displays any errors encountered during the calculation of earned value on the screen and creates an error log that can be saved for review.

You should correct any errors and perform the earned value calculation again. You can perform these calculations as many times as necessary.

The most frequently encountered errors are:

  • Actual dates that occur after the current status date.
  • Actual finish dates that occur before an actual start date.
  • The number of units completed either is a negative value or is greater than the original total for the work package.
  • The percent complete is either a negative value or is greater than 100.
  • The resource calculation file cannot be found.
  • The rate file cannot be found.
  • The earned value that is calculated for the current period is negative. (Cobra treats this as a warning rather than as an error since negative earned value could be the result of a corrective entry.)