Cost-ITD metrics question

user6287828

My question is about Project- Performance subject area in OBIA.

I am running some out of the box reports and I noticed that when I run reports for two Fiscal Periods the metrics value doubles (particularly ITD metrics). ( similarly triples - when I select 3 ) or is like 12 times when I run it for a year.

When I looked at the query of an adhoc report for two fiscal periods , I see that it gets twice the number of rows and aggregate it and hence it shows double the value of ITD metrics.

Has anyone else faced similar issue? If yes how did they resolve to get the correct value for ITD metrics when selecting multiple periods

Thanks