I’m suffering from a birthday hangover. Not the kind caused by too many flutes of champagne over a steak and lobster dinner. This case of the blahs is of the Peggy Lee, “Is That All There Is?” variety.

I turned 51 yesterday and, unlike my last birthday, found no reason to kick up my heels.

I know, I know. “Consider the alternative” and all that. But what’s so special about 51? There are no big parties, no pre-printed napkins or “The Big 5-1” balloons. No rhyming little ditties on yard signs like “Ain’t it nifty, look who’s 50!”

(Try rhyming anything with “fifty-one.” Go ahead, I dare you! It can’t be done. It’s like a prime number of words.)

Maybe the lack of a good ditty is the reason nobody gets worked up at this second-rate age. Besides, it’s such a letdown after all the hoopla the year before.

Three hundred sixty-four days before my 50th birthday, I started planning my half-century celebration with great enthusiasm. There were dozens of exciting possibilities, and I considered them all.

Should I take a trip? A cruise? Do something crazy like parachute out of a plane? Climb Kilimanjaro? Get a tattoo on my upper thigh? Pierce a scandalous part of my body? Bungee jump off the Eiffel Tower? Leave my husband and run off with one of those half-naked Abercrombie & Fitch models? (I’m kidding, of course. The thought never crossed my mind. Although, God knows, I’ve had plenty of chances. Those boys just won’t leave me alone.)

In the end, my 50th was a seemingly endless series of dinners out, family gatherings, girlfriends’ weekends, a vacation to Mexico (which I declared a birthday trip even though it was in March) and a party, to boot! It was a four-month Mardi Gras, without the flashing. (At least, none that I can recall.)

But this year? Nada. Zip.

Oh sure, there were lovely gifts, funny cards and a nice dinner. And I was grateful, I really was. But after last year’s Barnum & Bailey extravaganza, I woke up this morning singing “Send in the Clowns.”

That’s why I hereby propose that every birthday after 50 be a mandated blowout. Why wait until your age ends with zero to party like there’s no tomorrow? I’m talking about an annual hoo-ha, a shindig so big it takes two days to recover. Think Carnivale or New Year’s Eve in Times Square!

It’s a fact that the capacity to party is like memory function, muscle mass, the sex drive and every other human utility. It’s a “use it or lose it” proposition.

Therefore, just one night out of the year, I say we go for the burn. Let someone else be the first to go home. Edit phrases like “I’d better turn in, big day tomorrow” or “It’s past my bedtime” from our vocabulary. Go crazy, stay up past 11!

Moreover, there should be a compulsory birthday gift guide for each age after 50, much like the traditional wedding anniversary gifts dictated by Emily Post (first year – paper; 10th year – tin; 50th year – gold, etc.)

And because I’m making the rules, the designated gift for the 51st birthday will be diamonds. Yeah, that’s it! And nothing smaller than 2 karats. (Note: This rule is retroactive for 24 hours.) For the 52nd birthday, it’ll be a new kitchen. For the 53rd, a trip to London on the QE2. Every 54-year-old shall receive fistfuls of cash, in large denominations. And for the 55th, daily maid service and a landscaping team. At 56, nothing less than a personal masseuse will do. For the 57th, a new Jag!

And so it will go until the ripe old age of whatever. Each year will bring a raging bash and a fabulous gift. No longer will people have to wait a whole decade to be feted in the manner they so richly deserve.

Oh sure, we’ll all be exhausted. But at least when we wake up with a hangover, we’ll know we’ve earned it.