Thread:Semantic-mediawiki.org:Community portal/How to design a Semantic Wiki to best understand the concept of Time/reply (2)

What you're talking about at the end is, essentially, three-dimensional data: land area for country, for year, for viewpoint. SMW can only handle up to two-dimensional data per page, using the #subobject function. (Or you could use the Semantic Internal Objects extension, which does the same thing but with different syntax.) You could still store three-dimensional data, but you would need to use different pages for it: instead of just a page called "Kosovo", you would need pages like "Kosovo/2008" or "Kosovo/for Spain", or even "Kosovo/2008/for Spain". However, for your case you would presumably want the system to find the nearest year and that sort of thing, not just an exact year match; and I don't think there's any way to do that. So if you really wanted to get this working, you would have to create a page or subobject for every year and maybe even every viewpoint, even though it would involved a tremendous amount of redundancy.