Small Cars and Safety: Understanding Driver Death Rates

Despite ongoing advancements in vehicle engineering and safety technology, smaller vehicles, particularly Small Cars and minicars, continue to exhibit higher driver death rates compared to their larger counterparts. Recent data from the Insurance Institute for Highway Safety (IIHS) underscores this concerning trend, highlighting a persistent safety disparity based on vehicle size.

The latest IIHS driver death rate study, focusing on 2017 model year vehicles, reveals that small cars and minicars constitute a significant majority – 15 out of 20 – of the models with the highest fatality rates. Conversely, luxury SUVs dominate the list of safest vehicles, occupying nearly half of the top 20 spots with the lowest driver death rates. This stark contrast emphasizes the inherent safety advantages associated with larger vehicle size.

Joe Nolan, senior vice president of vehicle research at IIHS, points out the fundamental reasons behind this safety gap. “Smaller vehicles inherently provide less protection for occupants in the event of a crash. Their lighter weight also means they bear the brunt of collisions, especially when involved with larger, heavier vehicles,” Nolan explains. This physics-based reality contributes significantly to the elevated death rates observed in smaller car categories.

Examining the data more closely, the IIHS study reveals that minicars have the highest driver death rate among all vehicle categories, with 82 fatalities per million registered vehicle years. In stark contrast, very large SUVs demonstrate the lowest rate, at just 15 fatalities per million registered vehicle years. The overall average driver death rate for 2017 models stands at 36 deaths per million registered vehicle years, a notable increase from 30 for 2014 models and a low of 28 for 2011 models. This upward trend aligns with a general increase in U.S. traffic fatalities during the study period of 2015-2018 compared to the preceding four years (2012-2015).

The variation in death rates among 2017 models is substantial, ranging from zero fatalities for several top-performing models to a concerning 141 deaths per million registered vehicle years for the 2017 Ford Fiesta, a four-door minicar with a “marginal” rating in the IIHS driver-side small overlap crash test. Alarmingly, half of the models with the highest death rates in 2017 were also among the worst performers in the 2014 study, indicating a persistent issue with certain vehicle models and classes.

Since 1989, IIHS has periodically calculated driver death rates, providing valuable insights for consumers. These rates focus exclusively on driver fatalities to ensure consistent comparison across vehicle types, as every vehicle has a driver, but passenger presence and numbers vary. Data on fatalities are sourced from the federal Fatality Analysis Reporting System, while vehicle registration data is provided by IHS Markit.

Driver death rates serve as a crucial complement to vehicle safety ratings, offering consumers comprehensive information for informed car purchasing decisions. While IIHS safety ratings are designed for comparisons within the same vehicle size class due to variations in kinetic energy during crash tests, driver death rates allow for cross-class comparisons. However, it’s important to acknowledge the limitations of death rates as a comparative tool. While they are adjusted for driver age and gender, they do not account for other potentially influential factors such as driving speed, daily mileage, and road types.

To investigate the impact of mileage, IIHS conducted an additional analysis comparing driver death rates per 10 billion miles traveled. Collaborating with the Highway Loss Data Institute and utilizing odometer readings from CARFAX, the study found that mileage data largely supported the initial findings regarding vehicle size and safety. Interestingly, sports cars and luxury cars, typically driven fewer miles annually, showed relatively higher death rates using this alternative metric, while pickup trucks exhibited lower rates. However, the ranking of individual vehicles within each category remained largely consistent regardless of the method used. Consequently, IIHS continues to prioritize the registration-year method for publishing make and model results.

Luxury vehicles consistently demonstrate lower death rates compared to non-luxury vehicles of similar sizes. Nine of the 20 models with the lowest death rates are luxury SUVs, with additional spots occupied by midsize luxury cars, minivans, and very large SUVs. This advantage is often attributed to the inclusion of advanced safety technologies in luxury vehicles, such as blind spot warning and lane departure prevention systems, which are not as commonly available in less expensive models.

Despite the general trend, some small cars defy expectations. The Volkswagen Golf and Nissan Leaf stand out with remarkably low death rates of 0 and 5 per million registered vehicle years, respectively, regardless of whether measured by registered vehicle years or miles traveled. These figures are significantly lower than the overall small car average of 61 deaths per million vehicle years. The Golf’s performance is particularly noteworthy, considering its 2014 version was among the worst performers before a redesign in 2015. For the Nissan Leaf, an electric vehicle, the lower death rate might be related to driving patterns and environments typically associated with electric vehicle usage.

The latest driver death rates are calculated based on fatalities occurring between 2015 and 2018 for 2017 model year vehicles and earlier models with similar designs and features. Including older, equivalent models expands the sample size, enhancing the statistical reliability of the results. To be included in the study, a vehicle must have accumulated at least 100,000 registered vehicle years or recorded at least 20 driver deaths during the study period.

In conclusion, while advancements in automotive safety have benefited all vehicle categories, size remains a critical factor in crash protection. Small cars, despite improvements, continue to present a higher risk to drivers compared to larger vehicles. However, exceptions like the VW Golf and Nissan Leaf demonstrate that focused engineering and potentially usage patterns can mitigate these risks even within the small car category. For consumers prioritizing safety, considering vehicle size and safety ratings remains crucial when making purchasing decisions.

(Table – as in original article)

(Table – Lowest rates of driver deaths – as in original article)

(Table – Highest rates of driver deaths – as in original article)