Two operators can post the same average 12-month cumulative in a county and be nothing alike. One drills 30 wells that all land within 15% of each other. The other drills 10 monsters and 20 dogs that average out to the same number. If you're buying the next 15 wells, or lending against them, that spread is the whole story — and it never shows up in a single headline number.
Most benchmarking stops at the average. Averages are comforting and misleading. The question a buyer or lender should actually ask isn't "how good is this operator's typical well?" It's "how confident can I be that the next well looks like the typical one?" That's a question about distribution, and the record can answer it.
Pull the whole book, not the highlight reel
Start by pulling every well an operator has completed in a target county over a defined vintage window — say, the last three years, so completion technique and spacing are roughly comparable. For each wellbore, normalize the production history to a common yardstick: 6- or 12-month cumulative oil, or barrels per lateral foot if the laterals vary. Now you have a population, not a talking point.
With the population in hand, the questions get sharp:
- What's the median 12-month cum, and how far is it from the mean? A mean well above the median means a few big wells are carrying the average.
- What does the spread look like — the gap between the 25th and 75th percentile?
- How many wells fell below, say, 60% of the operator's own median? Those are the misses, and their frequency is the risk you're actually buying.
Asked conversationally against the Wellsite data lake, this is a single line of questioning: rank the operator's county wells by 12-month cum, show me the distribution, and flag how many landed below a threshold. You're not building a spreadsheet — you're reading a shape.
Tight book vs. wide book
A tight book — results clustered around the median, few big misses — tells you the operator has repeatable geology and repeatable execution in this county. The next well is likely to look like the last ten. That's the profile you can underwrite with a narrow confidence band and a single blended type curve.
A wide book — a handful of standout wells and a long tail of underperformers — is a different animal. The average might look fine, but the variance means the next well is a coin flip. Sometimes that's geology: the operator is drilling across a fault or a facies change and half the acreage is better than the other half. Sometimes it's execution: a landing-zone change, a completion-design experiment, or a contractor swap partway through the program. The record won't always tell you why, but it will tell you the spread is real — and that's enough to change your bid.
Separate the acreage from the operator
Before you blame or credit the operator, benchmark their wells against the county average and against the direct offsets. If an operator's wide spread simply mirrors the county's own spread, the variance is geologic, not managerial — the whole area is heterogeneous, and any operator would see the same scatter. But if the operator's spread is wider than the offsets around each of their wells, the inconsistency is theirs. Same the other way: an operator whose wells are consistently tighter than the surrounding scatter is genuinely de-risking through execution, and that's worth paying up for.
Watch the trend inside the spread
Variance isn't static. Sort the operator's wells by completion date, not just by size. A book that starts wide and tightens over time is an operator climbing the learning curve — the early misses were experiments, and the recent wells are converging. A book that starts tight and blows out is the warning sign: they may have drilled their best rock first and are now stepping into marginal acreage, or they've changed a completion recipe that isn't landing. The recent vintage tells you more about the next well than the three-year average does.
What the number actually buys you
When you roll a package of wells into one decline curve, the average determines your central case — but the variance determines your downside. A tight book lets you underwrite close to the mean. A wide book forces you to weight the case toward the misses, because you can't cherry-pick which wells you'll get. Two operators, identical averages, different bids. The one who drills the reliable well is worth more, and now you can prove it from the record instead of taking it on faith.
Averages tell you what happened. Distributions tell you what's likely to happen next — and that's the number you're really paying for.