Hello, The proposal for aggregate records : https://forge.gridforum.org/sf/docman/do/listDocuments/projects.ur-wg/docman... specifies the StartTime and EndTime of the aggregation, but I need some additional clarification. It does not specify what timestamp is used in the original Usage Records to check wether the record is in the specified interval. I tend to compare with the EndTime of the job. Then it is at least finished. But EndTime is a optional property. Is anybody interested in aggregated records of jobs without EndTime? The other thing which is unclear is whether the comparison with StartTime and EndTime are inclusive or not. The example in the document tends to suggest it is inclusive.(although the hour 11 should be 23) <urf:StartTime urf:description="">2001-11- 01T00:00:00</urf:StartTime> <urf:EndTime urf:description="">2001-11- 30T11:59:59</urf:EndTime> It seems logical to me that the StartTime is inclusive, but for the EndTime it is less clear. If you want to select a month you can either select inclusive : 2001-11-01T00:00:00 <= "time of job" AND 2001-11-30T23:59:59 => "time of job" or exclusively for the EndTime 2001-11-01T00:00:00 <= "time of job" AND 2001-12-01T00:00:00 > "time of job" With the latter is easier to specify a period of a month, but I have no problem with the inclusive version. But I think it should be made clear in the recommendation. Best regards, -- Bart Heupers, HPCV Advisor, 31 (0) 20 592 8071, Science Park 121, 1098 XG Amsterdam