(I'll give the leap-day jokes a miss.)
Statistically, this is probably a little past the half-way point for me, at least in terms of life expectancy. Since my dad only lived to be 56, and his dad died sometime in his 60's (maybe early 70's) I can be accused of optimism if I call 40 "half-way."
In terms of physical ability I'm also past the half-way point. Oh, I may be able to push back the clock a little bit through healthy living for the next twenty years, but there's no going back to age 25 (not without blood-nannies, or something similarly techno-miraculous.)
All of this might be kind of depressing. It's also a very inaccurate way to look at things, since the only person for whom any of this is true is me. It's a very selfish perspective, and it's not worth dwelling on. Let's consider some others:
My oldest daughter has had 12 years of shared experience with me. Even if I only live to be 56, this birthday is still a couple of years shy of the half-way point from her point of view -- more if you account for the fact that she doesn't really remember the first three.
My youngest son has had 5 years with me. If I live to be eighty (look! Optimism!) then the times we've already shared as of this point represent only one-ninth of the times we can share going forward.
Sandra and I have enjoyed fifteen years together. If we get another forty, then obviously today isn't anywhere near the half-way mark.
I suppose the oldest of my siblings, who joins me in her forties next year, can claim that this is pretty close to half-way for the two of us, but she's the only person I've known for that long (okay... there are aunts, uncles, and cousins OLDER than me for whom the halfway point has long since fled... but let's not dwell on that right now.)
And now let's consider you, the reader. How long have you known me? Maybe five years? Perhaps eight?
I plan to keep cartooning up until the end. If I hold true to that (and the indications are that I will) then you and I haven't even hit the 20% mark. I may be "mid-life," right now, but I've got decades in which to continue building worlds in my head and then telling stories about them. This ride isn't half-way over. It's barely started.
That's my happy thought for my Birthday this year.
I feel: satisfied