I wanted to extend my 2d comparative visualization, so I started by converting from averaging the 2 sets to defining the rectangle which bounds the two sets, then plotting those along the z axis. This qudrangle view I hoped would make the data presented in my first comperative 2d visulization more clear and easy to follow.

select count(*) as count, sum(case when (title = "lord of the rings return of the king") then 1 else 0 end) as lotrrotk, sum(case when (title = "hobbit or There and back again") then 1 else 0 end) as hobbit, sum(case when (title = "game of thrones") then 1 else 0 end) as got, sum(case when (title = "name of the wind the kingkiller chronicle day 01") then 1 else 0 end) as notw, sum(case when (title = "american gods") then 1 else 0 end) as ag, year(o) as years, month(o) as months from title inner join activity on activity.bib=title.bib inner join collection on activity.item=collection.item where (title= "lord of the rings return of the king" or title = "hobbit or There and back again" or title = "game of thrones" or title = "name of the wind the kingkiller chronicle day 01" or title = "american gods") and year(o)>=2006 group by YEAR(o), MONTH(o) ASC limit 100

I used Processing and Peasycam.

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