There’s gotta be a formula. Somewhere some big-brain types are hunched over statistical software crunching numbers on the Big Question – and one that I, frankly, probably have wrong.

If I understand correctly cable operators get their revenue in two key ways – subscriber revenue through monthly service fees, and local and online ad revenue (my provider does an excellent job on their portal and is my default page for news, information and all things Britney – and I often click on the Expedia ads to see the latest $100 flights).

The big question? Which of the triple play services has the highest profit margin. Not top-line, as I am sure video has that because of tiered sales and ad revenue. I’m talking pure margin percentage – costs vs. revenue. Voice? Video? Or data? Here at the Hermes Compound, we have triple play from one of the Big Boys. And a glance at my latest bill shows an even split between TV and voice of about $62 and about 20 bucks higher split for internet, however we have two modems serving the office and the outside Man-Cave my son has dubbed “the Fort,” so internet is really about 20 bills less.

So…where’s the highest margin? While I doubt an op will come right out and say it, I am going with Internet service. Hey, the net is free. People want speed, and are willing to pay for it. Opening the pipe up can’t be too hard if you have the right gear for it, and as long as the coax in the home is sound and delivering. Now the downside of course is the back-end support help but with practically every state-level university cranking out IT grads like a 1920′s Henry Ford assembly line, my guess is that the average age – and salary – of the local cable troubleshooter answering the phone once you go through the 30 prompts is probably one-sixth their IQ. These are smart kids, and every time I have had an issue they have gotten to the bottom of it. And if not, the outsourced Indian contingent can usually nail it.

Now phone? Basically the same thing. However it seems phone problems require more truck rolls and aren’t as often serviced over the phone but in person. That’s gotta add up in man-hours, insurance, overtime, fleet upkeep. But the add-on features – call waiting, caller ID, additional lines, enhanced voice mail…all set up at the touch of a button also create a recurring line item on the invoice. And while I still can’t figure out how to delete a voice mail without listening all the way through the call, I’m pretty happy with my voice service too and will keep using it.

So where are the bucks being made? Which of the Triple Play is really “Triple Pay?”

The answer is, probably, all three. The guys running these systems are uber-smart for the most part and had this knocked years ago. Me? I’m just barely keeping up. But it’s fun to think about,. And for the record? I’m guessing “internet.”

Tim Hermes is CEO at Broadband Gear Report. Email him at timhermes@comcast.net.