This is true for me, ymmv.
Time seems to pass much more quickly as one is experiencing it when one is busy.
However, looking backwards, time periods that were chock-full of activities tend to lengthen. A point in time a year ago seems further in the past in a busy year than a sparse year. Almost as if your mind assumes some average activity density, then applies this to remembered activities to estimate time passage.
The absolute randomness of this observation should give readers an idea of my state of mind today.