If you have matched Months for that Year off course, It will map and will show the status for them. 2016 - Jan, Dec and 2017 - Dec. Then if you un select 2017 yes there is Dec for 2016 that is where it is showing. If 2016 - Dec is not mapped for 2016 then this will hide automatically that is how QIX works.
Finally, If we degrade to each then we can use Aggr(Dim,Dim) but with in selection we can't verify. But using Straight may be possible so even with Current Selection Box can offer the same if each not associate.
Before develop something, think If placed (The Right information | To the right people | At the Right time | In the Right place | With the Right context)