In this week's episode of Focused, Sean McCabe talked about how he uses his calendar not only to plan future events but record older ones. I do the same thing, but I've never written about the practice.

To me, the current moment is where my calendar transitions from a planning to an archive tool. I mean that I have time planned for the next week with projects I plan to work on and places I plan to be. However, that is only hypothetical in the future. I may plan to work on a client contract tomorrow afternoon at 14:00, but then again, maybe one of my kids will need me, or another client will call in with an emergency. Some days follow the plan. Others do not.

However, as part of my overall effort to track my time and attention, I'll adjust my calendar to match what happened as the day goes by (or at least at the end of the day). So in the moment of "now", my calendar moves from a planning tool to an archive tool.

So why the extra step? I find that recording in my calendar has several benefits:

Better Understanding
By recording how much time things take, I get a better understanding of … wait for it … how long things take. In the future, that will pay off with better estimates.
Reflection of My Actual Time and Attention
Maybe I planned to spend the entire morning working on the next Field Guide. But then, later, having to go back and change that block to reflect that, in reality, I spent the morning watching YouTube videos about USB-C cables, which forces me to reflect on whether I am spending my time wisely.
Catching Falling Plates
Going back to that earlier example, I may have a block of time set aside for that client contract. Seeing that I didn't get to that on a busy day gives me the opportunity to move that block into the future, back into planning, and making sure I don't drop the ball.
Easy Reference
Sometimes I do find myself trying to figure out what I was doing on a particular day. Having this data in my calendar makes that trivial.

Turning your planning calendar into an archive tool takes some extra work throughout the day (or perhaps just at the end of the day), but in practice, the amount of time it takes is just minutes, and I find that a trivial investment of time for the payoff to be worth it.