Depending on the software you might need to use financial periods.
What I am saying that as per P3 they must be pre-defined by job, in P6 globally. That in these software to get the correct distribution for past performance you must update strictly as per financial periods and then post the update every time and your reports will be limited to a single pre-defined period to get correct past performance distribution, otherwise why so much fuss about it. With these software you will be able to generate past performance reports but only when using a report period equal to the pre-defined the distribution will be correct.
In other software you can get reports for any financial period [can be any, not merely a few hundreds different financial periods; every 2 hours, every day, every month] defined after you update your job in any combination of period updates. The following report is for a period of 2 hours, you can see the correct past performance for 2 hour detail. I updated the job using a weekly update but one activity was reported working only 2 hours a specific day and it shows correctly, is simple math other software can do. Look at November 8, activity one worked only 2 hours that day and reported some cost during these two hours [8:00 to 10:00 am $300].
Past performance is not only about the distribution of costs per past periods but also about the actual production per period, necessary to show changes in productivity on a claim. Some software are not good at keeping detailed records for past performance and their reporting is limited.

I wonder about Asta PP because on their literature I saw an excellent example of detailed activity updating and reporting.
