I often recall which years were good ones for me, or at least which were particularly memorable based on what happened in the year, or what my predominant emotion was at the time; to the best of my memory, was I happy, or frustrated, or tired most of the year? Based on my perception, I make the determination as to whether the year was 'good', 'bad', or 'uneventful'.
It's also possible for a year to appear to be bad during the time I was experiencing it, but in hindsight, turned out to be a good year after seeing the eventual results. I take this into account also. In fact, some of the worst years actually turn out to be good years in hindsight.
I found that the common theme occurring among the favorable years were that these were the ones where I felt the most alive, carefree, and passionate. They were also years where I achieved some profound insight, or had some experience that had a big effect that stayed with me up to the present. Here's a list of my 'good' years starting from 1985 up to the present. The years in bold text were ones that were particularly memorable.
Are you in a good year?