Don't know how to put it... but I gave away the first genius masterpiece score to Gunnm already. There's also one firm masterpiece Kyou kara Ore wa!! .
I failed to find something really good in Summer 1992 season, Kurenai no Buta is the best title among the decent ones, but I still don't consider it a masterpiece.
Yokoyama Mitsuteru Sangokushi is not as spectacular as Sangokushi movies, but I was interested in learning the roots of the story so much that I enjoyed it substantially nevertheless.
I can highlight two borderline masterpieces - Osu!! Karate-bu and Chibi Maruko-chan Movie with original work always taking precedence over recurring one of equal score.
First of all, with 100 titles after filtering this is getting totally unreadable, so from 1990 I'm moving to coverage per season rather than per year. In 1989 there were quite a few surprises for me as I could call as many as five titles borderline masterpieces Venus Senki , Hoshi Neko Fullhouse , Majo no Takkyuubin , Tezuka Osamu Monogatari: Boku wa Son Gokuu , Assemble Insert with first one turning my personal favorite from this list.
Did not expect to see Hadashi no Gen so early, but yeah, it's definitely a firm masterpiece and the winner, also only the second anime I rated as 8. However, I can call another anime within a year a masterpiece for the first time - and it's Time Slip Ichimannen: Prime Rose . Good times seem to be finally coming for anime !
Could not call anything a masterpiece in 1982, sadly. The anime I enjoyed the most is Sasuga no Sarutobi . Hopefully, highlighting it advances its translation .
I ended up with choosing just one title as masterpiece - Jarinko Chie - even though there were quite many titles close to that and also some titles without translation that could also fit my criteria otherwise