After all, the yellow column on the right-hand side of r/ACT ("Prep Materials") currently has a link to the December 2015 test only, and this post currently includes 64 ACT tests (I wrote 65 in the title but it's too late to edit). Thanks! More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.