A guy walks into a whorehouse and picks out the prettiest girl in the place. They agree on a price and she tells him to meet her in a room upstairs. He goes up and waits for her arrival, but, much to his surprise, in walks a fat old man in a teddie.

“What’s going on?” the customer asks. “I paid for the beautiful woman I met downstairs.” “Sorry,” the old man replies, “You only get her during sweeps.”

Network TV is slowly being “swept” away.

Okay, so the analogy isn’t perfect and only some of us are whores. But the point remains: Sweeps, or, as I like to call it, Four Network Monty, is one of the forces that is slowly killing network television.

Sweeps refers to the three months a year when advertisers perform detailed studies of who’s watching what timeslots so that they can determine ad rates. It rears its ugly head the same months that your local eyewitness news team shows a sudden interest in breast enlargement surgery and thongs in high school.

You can sense its impending arrival when network presidents and schedulers, under tremendous pressure from advertisers and above, begin to announce their strategic moves: Yank the weak fledgling upstarts and double up on the proven and the sensational.

The result is a confusing star-studded quick-fix schedule that is completely unrepresentative of the network’s actual fare.

Consider one major network’s recent pre-sweeps announcement to move a certain first-year show back to Friday night where it originally premiered before it was moved for a short time to Wednesday, where it will be followed by a news magazine, which replaces a critically-acclaimed but slow-starting cop drama.

Meanwhile, they will pull a new show off Thursday and replace it for one week with a new show from Tuesday, after which they will fill the slot with a rerun of their biggest proven hit.

Confused? I work in the television industry and I could more accurately tell you the NBC Thursday night line-up from 1984 (“The Cosby Show,” “Family Ties,” “Cheers,” “Night Court,” “Hill Street Blues”) or the 1977 CBS Saturday Night line-up (“Mary Tyler Moore Show,” “Bob Newhart Show,” “Carol Burnett Show”) than I could any network’s line-up today.

No wonder new hits are fewer and farther between — viewers can’t find the shows they like. Even my TiVo’s Season Pass manager can’t keep up. It has stopped smiling and making that happy little “boop” noise.

Worst of all, come December, March and June, the battlefield is littered with the corpses of those which could have been — shows that were pulled for sweeps and cancelled shortly thereafter.

Yet, the list of hit series with slow starts is legendary: “Cheers,” “Seinfeld,” “Everybody Loves Raymond,” “All in the Family,” just to name a few.

Some needed time to find their audience; some needed time to find their voice. In today’s marketplace, they would have been replaced with a super-sized episode of “Extremely Queer Millionaire Makeovers.”

I equate it to music. It took a few listens before I warmed to Bruce Springsteen’s “Born To Run.” Twenty-eight years later, it’s still an album I wouldn’t want to be stranded on a desert island without. Conversely, at first I really liked Ricky Martin’s catchy “Living La Vida Loca.” Two weeks later it made me want to rip my ears off.

Too often, the precious time a fledgling show needs is sacrificed just to satisfy this antiquated ratings system. And there’s no excuse. My cell phone can take pictures and my car can tell me how to get to the Ahmanson, so clearly the technology exists to obtain a year-round, accurate reading of what the audience really watches.

And, please, let’s not hide behind privacy.

A) The information could be gathered anonymously and B) People would gladly share their most-personal viewing habits in return for better television. I don’t care who knows that I watch “Real Sex.” Just don’t yank my favorite show and replace it with “America’s Greatest Game Show Moments.”

I love network television at its best. It’s a medium that respects the writer and, to quote another classic show that started off with low ratings, it’s been “bery, bery good to me.” That’s why I want to see network television survive the onslaught of cable, Internet and video-on-demand.

I recently asked a friend of mine who happens to run a network, and who also loves television, why we can’t update our ratings system, when almost everyone agrees that it’s so terribly flawed.

He replied, “Because there’s no motivation for anyone to change it. The networks aren’t complaining, Nielsen isn’t complaining, and most importantly, the advertisers aren’t complaining,”

So, I’m complaining.

Steven Levitan is the executive producer of the Fox sitcom “Oliver Beene” — which is scheduled to return to the FBC line-up in January — unless, of course, it gets pulled for sweeps.