Digital log book
I have been using excel for the last 8 years as a digital back-up to my paper log book. It means that whatever bespoke stats I need to com up with, I can pull them out really easily. I also record interesting pax rides in it, but obviously I've set these to not count in the totals.
Bonus is that it's free. I keep a master copy at work and email regular updates to my private email address so no matter where I am, if I can get my email, I can get my log book and whatever detail I want from it.