It’s my birthday today. I am officially … older. And I can’t believe how old I am.

It seems like just yesterday it was yesterday.

I don’t know how this happened.

Maybe it’s that my watch is broken. Or it could be my calendar’s not working because I’m still using the one I got some time ago with the pictures of golden retriever puppies for the months of April and October.

In any case, it does seem like it wasn’t that long ago that I ran marathons, climbed Everest, swam the English Channel and invented sushi.  I may also have written great novels or at least a few really good sonnets.

Or maybe that was someone else.

That’s what happens when you get older. Your memory starts to go and you can’t quite tell the difference between the lies you make up and the lies other people make up.

What I’m sure of, though, is that there was a time when I thought that the age I have just reached was such a … umm, mature …. age that it was an age that my parents were, that U.S. presidents were or that people who played pinochle or canasta were. And yet I have now joined them — and I’m pretty sure of that because I regularly get the five percent discount at the supermarket on Thursdays, even though I keep hoping they’ll card me.

Many — that is, some — years ago, when I turned 30, I told friends who were worried about not trusting anyone over 30 to not worry about it. Thirty was only a number, I said, showing off my then-youthful mathematical skills.

And then on the morning of my 30th birthday, I woke up covered in locusts and also unable to figure out the tip when we were splitting the check. My friends, clearly, had been right.

When I turned 40, I realized that I had no friends anymore because they had all been eaten by locusts. I also realized I was about halfway through the normal lifespan and I had yet to go skydiving or completed composing a sonata or did any sonata composing at all while I was in the middle of skydiving.

At the age of 50, I finally gave up my dreams of playing in the major leagues. Mostly, this was because I could no longer find my Little League baseball glove. Glove memory is the first thing to go, of course. I was also starting to forget where I had left my sushi.

Ten years later, when I reached another milestone birthday, I decided that if 60 is the new 50, and 50 is the new 40, and 38 is the new 29, then I must be losing my once-youthful mathematical skills.

And now, here I am, at an even older age, a numerically significant older age, an older age that ends in a zero. I think I’m going to celebrate by composing a sonata. Or at least a sonnet. Whichever comes first.