http://www.newyorker.com/fiction/poetry/2009/05/18/090518po_poem_frazier
"And so, at last, I am turning forty,
In just a couple of days.
The big four-oh.
Yes, that is soon to be my age.
(And not fifty-eight. No way. That Wikipedia is a bunch of liars.)
Nope, not any other age, just forty.
What other age could someone born in 1969 (and not 1951)
Possibly be?
(And please do not listen to my ex-wife, that sad, bitter woman in her
late fifties.)
What does it feel like, old bones?
Yes, I have lost a step or two in the hundred-metre dash.
I accept these changes.
But if a guy says in a published poem that he is forty,
As I am doing here,
It’s obvious that must be the age that he is,
Officially."
--
gwern