The Cost Per Nut Formula: The Brutally Honest Dating ROI Metric

CPN = Total dating spend ÷ Total outcomes

That's it. Total spend in dollars, total outcomes as a count, divide, get a dollar amount per outcome. Compute monthly, quarterly, and lifetime versions if you want, but they all use the same one-line formula.

The simplicity is the point. Any metric with a complicated formula gets tweaked into uselessness within three months. CPN's brutal one-line definition is what makes it sticky.

Everything you wouldn't have spent if the date didn't exist. Dinner, drinks, transport both ways, cover, parking, the gift, the ticket, the corkage. The shirt you bought because of her counts if it wouldn't have been bought otherwise.

What doesn't go into spend: your existing rent, your existing phone bill, your existing gym membership. CPN is a marginal-spend metric, not a total-cost-of-living metric. Be ruthless about what's marginal.

Outcomes are whatever you define. Sex, kiss, second date, third date, relationship. The metric works for all of them as long as you pick one and hold it constant. Most guys settle on the obvious answer for their stage of life, and that's fine.

The mistake to avoid is defining the outcome retroactively, which is just rationalization. If your CPN looks high and you decide "actually I was counting third dates wrong, let me adjust," you've stopped doing math and started telling yourself a story.

Pure CPN is a dollar metric. The time-adjusted version divides total time spent (in hours) by total outcomes. It's the second-most-useful CPN-family number.

Time CPN matters because two guys can have the same dollar CPN and live wildly different lives. Guy A spends $200 per outcome in two hours of effort. Guy B spends $200 per outcome over forty hours of texting, three dates, and a road trip. Same CPN, very different efficiency.

If you only have bandwidth for one second metric, make it time CPN. The combined picture of dollar CPN and time CPN tells you more than ten dashboards.

Aggregate CPN tells you what you're spending. Per-girl CPN tells you who you're spending it on, which is where the real insight lives. Compute CPN at the girl level and you'll usually find a power-law distribution: one or two girls are absorbing most of the spend, and they're rarely the highest-outcome girls.

Once that distribution is on the screen, the action items write themselves. The high-spend, low-outcome girl gets a hard conversation or a smaller share of your time. The low-spend, high-outcome girl gets noticed. The middle gets a wait-and-see.

Cheat one: not counting nothing dates. A coffee date that ended at the door still cost you money and gave you zero outcomes — and most guys conveniently forget to log it. Without those rows, your CPN looks like fiction.

Cheat two: outcome-stuffing. Counting every kiss as an outcome works until your CPN starts being measured against your buddies' and you realize the variance is mostly definitional.

Cheat three: spend-deflation. "It was a work dinner that became a date" doesn't get half the dinner allocated to your CPN; it gets all of it allocated to your CPN. Be honest.