I keep records of my fishing trips for crappie, and theyre very similar to yours. I "had" a couple years of records on the 'puter and lost them when the dang thing crashed so I was reluctant to start more records but did after a bit of time.
Those records I lost actually told the story on when the fish moved in the water column and at what temps so it took ALOT of the guesswork out of finding the fish. I hated I lost 'em but that wont be the case now as I keep 'em backed up on a 1 gig memory stick now. Even though I only started this new record this past Jan/early Feb, I look for it to fill in the blanks for me starting next year.