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Introduction

In the podcast embedded in my previous article, I mentioned some of the changes I perceived in NASCAR over the past few decades. I surmised that NASCAR has transformed from a demolition derby-type event to a highly-engineered, much safer sport full of parity and excitement. In this short article, I will show some data that validates my observations.

Before I leave the topic of that podcast, however, there is a special video that I hope you watch. This GM Performance Motor Sports video shows how my coworkers prepare for an upcoming race. It also gives behind-the-scenes access to areas of our facility that are typically “no-photographs-allowed”! This great video shows advanced engineering in action at an amazing facility. This will also give you insights into how we crunch numbers to perform real-time analytics support for our racing teams.

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NASCAR Changes Over Time

When I began working with NASCAR data last year, some things surprised me. One of the biggest changes I noticed was that more cars finished races than when I was a kid. Additionally, there seemed to be fewer crashes and, correspondingly, fewer mechanical failures. It seemed like there were big changes in safety and improved mechanical performance.

Figure 1 is a monthly time series chart for three categories of race finishes. The first category is the percentage of drivers (and cars!) finishing the race (dark grey). This metric rose from a low of 40% in the early 1950s to over 80% by the 2020s, which means the drivers and cars perform more reliably from race to race.

The second category depicts engine failures during the race (light blue). Between the 1950s and mid-1970s, engine failures rose from about 5% to 20%, with increasing variation approaching 30%. Somehow, in the mid-1970s, the engine failure rate began continuously dropping from 20% to a low of 2% by the 2020s. Not only has the overall rate of failure decreased, but so has the variation from month to month. If you notice, there is a strong relationship between the first two measures. As the rate of engine failures decreased, the rate of drivers finishing races increased.

Finally, the third category depicts the percentage of races that ended in crashes (dark red). The most notable feature of this category is that it took until 2001 before the variation and overall rate of crashes began declining. As shown in Figure 1, using the HANS devices might have been instrumental in reducing race crashes. I can only surmise that that device gives the drivers more stability in sketchy situations, thereby allowing them to avoid race-ending situations.

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Final Thoughts

I think I might write a series of simple articles on topics like this. Having over 75 years of data allows me to examine how the sport has changed over time. By critically evaluating the data, I might uncover insights that could help our drivers win more races. Thanks for reading!