Hmmm, I want to play (if just for the amusement of having the smallest number -- my commute is less than 2.5 miles one way), but I've just been logging all my mileage (a whopping 55 miles, ha) collectively this year, whether I've ridden to work, or just to the park, or to the beach, or the bar, or what.
Often I'll run an errand or go out to eat before work, and then do some pub-hopping after work, and then head home. Can I count that? What about trips to the grocery store? Should I just allot myself 4.75 miles for each day I ride both ways and not include other stops? Am I overthinking the absolute hell out of this? Yes.
But really, help a newbie out, here!