Did Stage Racing Produce More Cautions Because Drivers Raced Harder?

One of the theories behind stage racing is that drivers would race harder to get stage points. That should theoretically be reflected by the number of cautions. Cautions appear to be up in 2017. Are they? And can we attribute the change to stage racing?

Let’s go to the data.

Are Cautions Up?

I’d argue no. A number of writers noted that the absolute number of cautions is up by about 10% over 2016. This is true. There were 296 total cautions in 2017 and 269 in 2016; however, let’s look over a longer range of time. This is data from 2001 to the present day.

On average, a 10% change in cautions from year to year is normal. (If you’re talking 300 cautions, a 10% change is 30 cautions; if you have one additional caution at every race, you’ve made your 10% plus a little more right there.)

The average number of cautions over the last sixteen years is 298. The largest number of cautions was 373 (in 2005), which was a 20% increase from 2004. The Coca Cola 600 had 22 cautions (15 more than in 2004); There were 10 cautions just between laps 115 and 240. Add to that a gain of 7 cautions in the Daytona 500 and 7 cautions in the Fall Bristol race and you’ve got the extra 10% right there. I looked for awhile to try to see if I could find the factors responsible for the big increase, like a lot of rookies (nope), but I failed.

The lowest number of cautions was 216 in 2012. Remember all the hew and cry about how cautions were falling in 2012 and everyone thought the races were boring because they had so few cautions?

In terms of absolute numbers, 2016 was anomalous because the number of cautions in 2016 was down (by about 10%) relative to 2013, 2014 and 2015. So if you look at it in terms of absolute numbers, 2016 is the oddball year and 2017 is right in line with the three years before that.

So you can’t really claim that stage racing had a huge impact on caution numbers.

Or Can You…?

You cannot compare apples to oranges. It is even worse to compare apples to giraffes. The lengths of races and even which tracks are included often change year to year. Laps run are not always the same as the laps scheduled between rain-outs and green-white-checkers finishes.

You’ll notice, for example, that in 2012, we ran 514 miles — a full Daytona 500 — less than we did in 2011. That was the year both Pocono races were shortened by a hundred miles, plus Fontana was rain shortened by 142 miles, plus the second Pocono race was shortened an additional 155 miles because of rain.

Thanks to the good folks at racing-reference.info, we can look at cautions a slightly different way: by calculating the percentage of laps run under caution, which adjusts for the fact that we ran different distances in different years. This is the NASCAR equivalent to inflation-adjusted dollars.

You’ll notice there’s not that much difference when you look at the numbers in terms of percentages.


But Even That Doesn’t Fix the Problem

One of the challenges for data geeks like me is that NASCAR keeps changing the rules. I’m not complaining, just noting that this makes the task of understanding the numbers they collect slightly more difficult. I’m going to propose that, going forward, we count cautions differently.

My proposal is based on the principle that all cautions are not equal. I divide them into two types:

  • Cautions NASCAR has control over, like competition cautions and stage breaks.
  • Cautions NASCAR doesn’t have control over: accidents, pieces and fluids leaking from cars, etc.

I will argue that if we want to understand how cautions affect racing, you can’t include the artificial construct of the NASCAR-determined cautions. Specifically, if we want to understand the impact of stage racing, we need to take into account how stage racing changes the meaning of the caution numbers.

So I went back and tabulated the cause of every caution for the last few years. I’ll start by showing you the data from 2017. The figures next to each type of caution are the absolute numbers of that type of caution.

There were 69 stage cautions and 7 competition cautions for a total of 78 NASCAR-determined cautions our of the total 296 cautions. That’s more than a quarter (26.4%) of all cautions for the seasons.

We have no stage-end cautions and an average of 15 competition cautions for the three prior years. Cautions that NASCAR has control over were only about 5% of the total cautions before stage racing.

I would argue we shouldn’t include NASCAR-determined cautions in the total caution count. They are (almost all) about in advance and there are a lot of them. Look at the percentage of cautions the different types made up in 2016 and 2017

There were more stage-end cautions in 2017 than there were debris cautions in 2016 (and almost as many as debris cautions in 2015).

I claim that there were fewer cautions in 2017 in 2016. Counting only cautions out of NASCAR’s control, they are down from 255 in 2016 to 220 in 2017.

So What Impact Did Stage Racing Have?

The reason we care about cautions is that we’re trying to determine whether stage racing made a difference. So let’s look at what I argue are the actual cautions. I grouped infield fires, police pulling drunk people down from fences, uncontrolled tires, etc. as ‘Other’. The group ‘stalled’ includes both stalled and slow cars.

I just lectured you about only comparing two years and here I am doing it. So let’s look at the last four years. Here are the number of cautions for each type of accident.

Accidents & Spins

The biggest contributor to cautions is (unsurprisingly) accidents. In absolute terms, we had almost the same number of accidents this year as last: 168 in 2017 and 163 in 2016. That’s only a 3% increase. The number of accidents has been trending upward.

The number of spins is fairly small, but they were the same in 2016 and 2017 at 20 spins each.

If you count spins + accidents as a measure of the intensity of racing (are drivers taking chances and/or driving aggressively?), the results are interesting in that there isn’t much change. The increase from 183 to 188 (2.7%) isn’t significant. This number has remained in the 180-190 range for the last four years. I’d like to argue that you could say that drivers are getting better and there are fewer single-car accidents (i.e. spins); however, it might also just be that drivers are getting better at taking other cars with them when they mess up.

I argue that tells us that stage racing didn’t cause more accidents. The probability of drivers being more aggressive to get stage points is offset by the need to not wreck — especially knowing that even a fairly soft wreck might end up with your car being retired.


Here’s the other interesting thing from this graph: Debris cautions are down by 62% from 2016 to 2017 — and that’s with the number of accidents (the most likely origin of debris) increasing by less than 3%. In 2016, there were only four races at which there were no debris cautions. In 2017, Jacques Debris missed 21 races.

2016 races that had debris cautionsI’ve put a full summary of the debris cautions in a very large graph at the bottom, but here I compare the frequency of debris cautions for 2014 and 2017. This is a histogram, which gives you the frequency of occurrence of an event. For example, there were 21 races with no cautions in 2017 (the large orange bar at left) compared to 5 races with no cautions in 2014.


Total debris cautions are down 75% from 2014; however, the drop from 2016-2017 was much larger than previous year-to-year drops. This doesn’t tell us anything about the drivers; however it does suggest that the damaged vehicle policy implemented in 2018 is having an impact.

Stage racing may contribute in that the time between stages gives NASCAR a breather that allows them to do some track grooming (like Zamboni breaks at ice hockey games) and do a once-over of the track to get anything questionable out of the way before racing resumes.


  • We should stop counting stage-end cautions in the running caution count because it’s misleading. They will likely make up 20-25% of cautions as long as we stick with the current format.
  • The argument that stage racing is responsible for increasing the number of cautions in 2017 is
    • true only insofar as there were 69 stage-end cautions, which upped the total by 10%.
    • false if you omit stage-end and competition cautions. That results in a 13% decrease in cautions.
  • Accidents
    • They are a rough measure of how hard and how many chances a driver takes during a race. Alternately, if you’re the one taken out, they are a measure of how boneheaded your competitors are.
    • They are the largest contributor to the total number of cautions at 50% – 65%
    • They vary by about 8% a year over 2014-2017 (average: 156; min 144; max 168)
    • The data don’t support the argument that stage racing has made drivers race harder. Drivers have to balance aggressive racing with being around for the subsequent stages and the end of the race.
  • Debris
    • Debris cautions are way down in 2017 relative to 2016 (43%).
    • Debris cautions are down by 75% since 2014.
    • The most likely cause for the significant decrease in debris cautions is the damaged vehicle policy, with the ability to scan for debris during stage-end cautions also potentially contributing
  • The Future
    • Martin Truex, Jr. has called on NASCAR to raise the minimum speed to keep slower cars from getting in the way.

Bonus Big Graph

This was large enough that I didn’t want to stick it in the main text, but here’s the debris cautions plotted on the same vertical scale. In 2014, there were 7 debris cautions at a single race. In 2017, the race with the most cautions had only 4.





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  1. Serious data crunching….here’s a few things to think about. First, it is an issue when a car spins and the caution flag comes out immediately. Too often we’ve seen single-car spins, with no contact, and a clear track (car that spun is clear and away from racing line) result in a caution that is SO unnecessary. It’s tough for the car/driver that has the problem as far as recovering from the situation, but it really needs to be looked at closely and reduced or eliminated as a disruptive influence on the flow and outcome of races.

    As far as stages, I believe that these “contrived” cautions have had far too much impact on race outcomes. From pit speed violations to any number of other issues, the only right way to end a “green-checkered” stage is to pit the cars and have them resume their relative positions (prior to the caution) once they’ve left the pits. Instead of rushing pit stops, allow a set time to pit–as long as the car leaves before that time expires, it lines up where it was before the stage ended. If it’s a 20 second or 30 second in-pit time, that means no reason to speed, no loose lug nuts, no fuel spills, etc. Run past the in-pit time, and the car loses it’s spot and lines up at the back of the field.

    The one exception to this scenario is any cars which choose not to pit at the end of the stage–those cars would restart ahead of the stage winner and any cars that were ahead of those not pitting for the stage break.

    Another part of the stage break would be that cars, once leaving their pit, would pull up in line behind a stationary pace car at a designated location on the track–this would include cars not pitting, so that they would already be at the head of the field for the restart. Once the lead lap cars were all pitted, the pace car would then bring the field back to caution speed, until NASCAR signals the race is ready to restart. The effect of this would be to reduce the number of “wasted” laps counted under the “stage” caution (I recall some cases of 7 or more laps under caution for a short-track stage break).

    Finally, I would like to see an end to the mayhem of racing out of the pits in regular yellow/caution pit sequences–other forms of racing use a system in which the cars go immediately to a single line out of the pits, and as a car leaves it’s pit box, it must yield to any car already in the single-file lane at “control” speed–that is to say the car leaving it’s pit to enter the line cannot cause a car already in line to have to brake, maneuver, or otherwise reduce it’s speed, and failing to enter the single line before a designated distance from it’s pit box then can result in a penalty. This may also dictate the need for a new pit-lane speed control method, as used by other racing organizations, where an engine speed limiter/gear combination is used to manage speeds in the pits. How to make it precise enough so that no one is left at a disadvantage is one of the understandable concerns with this approach. The pit lane speed penalty is something that needs to be taken out of the mix–I believe technology CAN achieve this.

    I know that’s putting a lot on the plate that no one was expecting!

    • Wow! That is a lot of ideas. I tend to agree with you about the game playing off pit road and the speeding penalties. There a lot to digest there — you’ve obviously thought this through. Thank you!

  2. Lot of much needed data crunching and analysis here. Thank you. Two additional things this nerd would like to see now that you have the data is a combining of the bonus charts so that bar graphs for the three year period would be side by side for each track. Be interesting to see if that shows anything.

    The $64,000 one would be an analysis of debris cautions in the final 10 Laps of the race. We all know the “perception” just wonder if the data supports it.

    Again great job. Enjoy the site! Keep up the good work.

      • Interesting statement from Steve O’Donnell via Bob Pockrass: “NASCAR will not change the format as far as counting caution laps between stages, NASCAR EVP Steve O’Donnell said. He said they will try to shorten the length of time of those cautions.”

        I’m curious what precipitated this.

  3. Nascar has control over cautions that involve spins. Data on cautions is going to be misinterpreted if you think otherwise.

    Anyway, detailed analysis is great to see though. Thank you for posting.

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