SSAS is a periodic snapshot the right choice

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I'm a newbie to SSAS. I have a database which has an agreement table in which the status of the agreements changes over time. This is stored in the agreement log. the status can be any combination over an extended period of time. One set of questions I will need to answet are how many agreements are of a given status and also to show trends in the status over time. I'm reading Kimball and periodic snapshot seems to be the best fit but I'm at a loss how to design the fact table. Do I preaggregate the data into periods broken down by status? And then how do I manipulate it in SSAS and how do aggregations work as it's more like a bank balance. I sort of get some of the concepts but I'm still pretty confused.

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Agreed, this is a good case for Periodic Snapshot.

In this case, you need a status dimension, and a fact with a period indicator. Your reports will also need to filter on the period.

ETL is a bit more complicated, as during the current period, you clear down and reload the current period data. Previous periods to the current one are fixed. Obviously, you lose visibility on statuses that change multiple times within a period, so the period should be chosen based on how quickly the data changes as well as how often its reported. This is also why Periodic Snapshots are often used in conjunction with transaction fact tables