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In a slightly different context, from time to time I get out my old flying logbooks to reminisce over. Electric logbooks hadn't been invented when I started so and having set off with pen and paper I kept going with it until I got an iPhone. With the iPhone, I can fill it in as I go along but keep multiple back-ups. At some stage, I'll have a print fest so I'll be able to use them to embellish a few stories.
Anyway, if your records are important to you, it might be worth thinking about how you will continue to access them in future years. Garmin may change the format of their site/have a crash/go-bust etc. If you keep excel files on your own machine, how future proof is the format?
I guess that even the ink on printed pages can fade. Hopefully at a slower rate than my memory...
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