It was the Mr. Drysdale crack that finally did it. Suddenly I came to the realization my jokes may be aging faster than my audience. The catharsis came last week when my 12-year-old approached me in search of yet another loan against future earnings. The Mills girls pull in a cool $2 a week for helping fold laundry and sundry small chores around the house. There was a time when that was wholly sufficient to cover their little-girl fiscal needs, but it’s been some time since Mills Child One has been able to live within that particular budget. She has taken to begging additional cash under the pretext of a loan against her future allowance. At the rate we’re going I should be drawing a portion of her paychecks until she’s well into her 30s.But I digress.MC1 was hitting me up for a five-spot when I facetiously asked, “What am I, your own personal Mr. Drysdale?” It was just the sort of spontaneous pop culture bon mot upon which I’ve built my reputation and I expected a hearty laugh. Curiously enough, what I got was the blank and impatient stare of a 12-year-old who had absolutely no idea what I was talking about.“Get it?” I prodded. “Mr. Drysdale, the banker on ‘Beverly Hillbillies.’ I can’t believe you’re not laughing at that.”“Make it $10 and I’ll laugh,” said my now-second favorite daughter.After a bit of reflection I realized there was no way I should expect someone born in 1995 to appreciate a reference from a television show that went off the air nearly a quarter-century before her birth. Then I started wondering what other pop culture references may no longer be hitting the mark with my audience. Obviously, the two preteen girls on my home front are cultural desert ground for a man of my age. I like to think of myself as relatively young and hip, but the great bulk of my pop culture experience goes back 20 years and beyond. Calling an overly enthusiastic school principal Mr. Woodman (get it? the principal on “Welcome Back, Kotter”) or accusing a particularly hostile friend of “going all Macchio” on her (as in Ralph, the Karate Kid) only serve to amuse me, which is fine at home, but may not serve me particularly well in the outside world.The more I look around the more I realize the once-steadfast points of reference that once established my pop culture superiority have gone the way of turntables and network television. I work in a newsroom made up largely of people born after the moon landing or, more importantly, the release of “Smokey and the Bandit II.” There are people I speak with on an almost daily basis who are too young to have a favorite Monkee (Mike Nesmith, obviously) or to have lost money on an ill-advised “Battle of the Network Stars” wager (damn you, Robert Conrad). I recently spoke with a teacher who didn’t know Ron Howard had been an actor. I question whether someone too young to recall “Happy Days” should be allowed to teach our children.I suppose the answer is to update my reference points, but that’s not as easy as it sounds. Pop culture moves faster than it used to and there’s a whole lot more of it. About the time I come up with a good Chris Brown punch line he’ll be opening for that Japanese fiddler at Branson. I’d make a crack about Timbaland, but I’m not entirely certain what it (he?) does. And forget about the movies. By the time I’d perfected my “I Drink Your Milkshake” repertoire, the movie was on video. That fabled 15 minutes of fame has shrunk to about 30 seconds and I lack the time or desire to keep up.So it looks like I’m stuck with a noggin full of John Sebastian and “One Day at a Time” references, like some Burgess Meredith character slightly out of step with the day and all the more unpleasant for it. My older friends will still get them and the younger set, well they can either Horshack up or go all Macchio on me. Either way, I’m amused.