May 2024

Drilling advances

Gauging how far drilling and productivity have come
Ford Brett, P.E. / Contributing Editor

It’s with sadness that I am now trying to fill Jim Redden’s shoes. He did yeoman’s work chronicling drilling advancements. But, I promise I will try my best to build on Jim’s legacy by chronicling Drilling Advances and acting a little bit as the “recording secretary” for our important craft. 

To kick off my attempt at filling Jim’s shoes, it seems like it would be a good time to assess just how much drilling HAS advanced in recent years. Maybe that can help inform us on how we can all help advance drilling even further.   

Things change: 25 years of U.S. drilling data as a starting point. One fortunate thing about U.S. drilling statistics is that they have been consistently and completely measured for almost 75 years. These measurements let us compare high-level drilling performance over time and can provide insight into why drilling has advanced, and maybe how we can get even better. (Note: data like this exists for other regions, but it is not as easily found and has not been measured consistently for nearly as long. In future columns, we’ll get to areas outside the U.S., but what these data show is interesting enough).   

For over 75 years, U.S. statistics for total number of wells drilled, footage drilled, and active rig count are quite accurate. Fig. 1 summarizes just the last 25 years of one important (but not the only) OUTPUT drillers produce—hole. (Note: in future columns, we might get around to seeing what we can learn from older data). The source of these data is from well permits filed with the various state or federal authorities and is quite accurate—probably to much less than 1% error.     

Fig. 1. Wells and Total Footage in the U.S. for the past 25 years.

The figure shows that the number of wells (blue curve) and total footage drilled (green curve) have gone up and down—driven by changes in oil and gas prices. Duh.  We’re going to discuss what we can learn from all of this variation here, and in future columns.   

Talking about Advances, though—in terms of wells and feet drilled, it seems we haven’t advanced much in 25 years—the number of wells has gone up and down, but it is lower now than in 1998.  Total feet drilled have gone up and down over those 25 years, but advancement has averaged 2% improvement per year. Big deal. In terms of wells and feet drilled, it seems like we’ve just been treading water.   

But… to really measure advancement, you need to measure productivity…  that means we need to know how much OUTPUT get we get for the INPUT.  

Thanks to the good people at Baker Hughes, we also have quite accurate measurements of one important drilling INPUT—rigs. The black line in Fig. 2 shows how Active Rigs have varied over the last 25 years—certainly also because of changes in product price. Duh.   

Fig. 2. Active Rigs and Average Feet per day in the U.S.

Of course, rigs, number of wells and footage vary with each other… rigs make wells and feet. More rigs equal more wells, equal more feet. That all makes sense. We are missing one last piece of the puzzle, though, to really assess how drilling has advanced. 

Productivity = Output divided by input: You’ve come a long way baby. One more simple step can help us understand just how far drillers have advanced in the past 25 years—calculate average feet per day.  Take the number of feet drilled in the U.S. in a year, divide it by the number of active rigs, divide that number by 365 and that will show you the average productivity in feet per day for the entire U.S. fleet. The red line in Fig. 2 shows that calculation.    

This (pretty simple) line can tell us just how far drillers have advanced. And, over the last 10 years (by this productivity measure), drilling HAS advanced a lot. In fact, it has advanced 230%.  Ten years ago, rigs drilled wells at an average ~450 ft/day. In 2023, rigs averaged ~1,050 ft/day.  This data can also tell us some pretty interesting things about how fast we can improve—and about what makes us not improve.   

We don’t have time or space in this first column to cover all the interesting observations (and questions) this type of analysis raises, but here are a few starters:   

  • Every time active rigs go up in a big way, feet per day go down – why?   
  • Every time active rigs go down in a big way, feet per day go up – why?   
  • Average feet per day are pretty flat through about 2012, then they rocketed up by some 240% ,10% per year from 2012 to 2023 – why?   

In future columns, we’ll explore possible answers to these questions, and what it means about how we, as an industry, can get better.  We’ll also look at similar data from outside this U.S. example to others and hopefully figure out how it will help us all, as an industry, get better, faster.  So, as not to leave you hanging, here are three factors I’m pretty sure are involved… 

Technology: Improved downhole tools and surface equipment move the technical limit forward.   

People: Learning curve optimization and ramp-up takes more time when you release rigs / crews that need to “re-learn” when you bring them back.     

Process: Evolution of how we work together, and DO’s and DONT’s that aim for operational excellence, help us eliminate loss and waste. 

Drilling is a Team Sport on two levels. The Drilling Team organizes to build wells safely, effectively, and efficiently.  The larger project team—which includes our brothers and sisters in the geosciences, production, facilities and business disciplines—works together to add the most value from the project, as a whole. Drillers are just one of the disciplines on the larger team that it takes to actually get hydrocarbons—or geothermal energy—out of the ground… or for that matter, to put CO2 back in the ground. And we all mix technology, people and processes together while  we get our jobs done. 

More on all this later. In the meantime, I hope to start a conversation with any of you on how we can all help Drilling Advance. Please email me at, and I promise I’ll respond.   

About the Authors
Ford Brett, P.E.
Contributing Editor
Ford Brett, P.E. , is CEO of PetroSkills. He has consulted in over 45 countries, been granted >35 patents, authored >40 technical publications, and has served as an SPE Distinguished Lecturer, as well as on the on the SPE Board as Drilling and Completions Technical Director.
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