Franz said:
I would like to calculate, if the status of a summary task is more than 15
days behind schedule and for that purpose would like to compare the elapsed
days from start to Current date:
IIf((ProjDateDiff([Current Date],[Finish])-[Summary
Progress])<15,"red","green")
Unfortunately, can neither read the field Summary Progress nor calculate it
yet... any ideas?
Thanks in advance!
Franz,
First of all, Summary Line progress won't necessarily be to the current
date even if all tasks are "on schedule". Here is how Summary Line
progress is calculated by Project.
Summary Line Actual Duration = (sum of all subtask Actual
Durations)/(sum of all subtask Durations) x Summary Line Duration
It is debatable whether the method Project uses to calculate Summary
Line progress is valid or not. In most cases it is probably a reasonable
measurement but there are cases where it will not give a true picture of
progress. For example, if there are several milestones among the
subtasks, the summary progress will likely be skewed since milestones
have "0" Duration.
I believe most organizations use the classical earned value metrics to
determine how well a plan is progressing although in my opinion, cost
based SPI is NOT a good measure of progress. Nonetheless, if you do not
want to use earned value and have your heart set on measuring the
progress "quality" at the Summary Line level it will probably take
either more than one custom field formula or VBA to establish where the
Summary Line progress should be at any point in time compared to where
it IS at that point in time.
Hope this helps.
John
Project MVP
