Data Diving EPA’s 2021 Automotive Trends Report: Charting The Big Changes Since 1975

EPA’s 2021 Automotive Trends Report is out, and as usual, it is a treasure trove of statistics. I’m going to dive in and extract some key charts and summaries, as the whole thing is a bit much, although I do recommend reading it to properly understand the impacts technology and consumer preference have made on real-world fuel economy.

This is the single most important chart, as it sums up the story so far, since 1975. The plunge in weight and hp and the concomitant increase in fuel economy directly after the two energy crises is stark. 1987 set a record in fuel economy that would not equaled for two decades (2008), by which time weight and hp had increased substantially. Since then, weight has stayed roughly the same, but hp and economy continue to increase, thanks to technology improvements.

Of course economy would be significantly higher if weight had stayed at 1987 levels, but consumers have voted with their preference for larger and heavier vehicles, back roughly to 1975 levels.

We need to get terminology out of the way first, as it’s not necessarily logical. The sedan/wagon class is largely self explanatory, and includes all sizes of sedans/wagons, hatchbacks, two-seaters and such.

SUVs fall into either the car or truck category depending on some rather arbitrary metrics. Most 2WD SUVs with a GVW (gross vehicle weight, meaning maximum loaded weight) of 6,000 lbs or less are categorized as cars, while most  with 4WD or GVW in excess of 6,000 lbs are considered trucks. This is of course rather silly, as it means that essentially all Subarus are trucks, as one example). Given that over 50% of all vehicles now have 4WD and the preponderance of that in SUVs, the number of car SUVs is quite limited. But that’s how it works.

This chart shows the changing percentages of production share and fuel economy of these five categories. Contrary to popular myth, the share of pickups of the whole market has not really changed much, since the overall market has grown so much over the decades. But then neither has their fuel economy since 1980, as that undoubtedly reflects the change in the composition of the pickup market, which once had a large percentage of compact models, and the full size ones have grown in size, weight and features (on average). Other categories have shown larger improvements in economy.

This shows the distribution by vehicle type by manufacturer, arranged from left to right according to CO2 emissions, which is of course a direct reflection of fuel economy. GM, Ford and Stellantis unsurprisingly are all at the far right.

We see here that pickups have had the biggest weight problem since 1975. Again, the decline of the mini/compact pickup segment is undoubtedly the biggest cause, along with the increase in crew cab models, 4WD and feature creep. Note that there has been some reduction in the past few years, thanks to Ford’s aluminum body, other efforts at weight reduction, and an increase in the “compact” pickup sector.

Pickups have also had the biggest increase in hp since 1975.

It’s important to point out that massive increases in maximum hp does not directly correlate to comparable decreases in economy, thanks to dramatic technology improvements. This chart shows that was much more the case in 1978 (dark blue) compared to 2020. Nevertheless, there is a correlation, and it and higher weight have directly contributed to greater CO2 emissions (worse fuel economy).

Of course all that increase in hp has had a concomitant effect on acceleration.  Average 2020 vehicle 0-60 time is 7.8 seconds. In 1981 or so, peak “malaise”, that appears to have been about 16.5 seconds, so the decline since then is fully over one half.  Once again pickups had the biggest decline.

Here’s a more detailed listing of some of these categories year-by-year.

Technology has of course been the sole driver of improved economy, given the growth in weight and hp. Here’s a chart showing the various primary technology types and their adoption by manufacturers.

Self explanatory.

This one is interesting, showing the changes in key metrics for gas engines. It shows the drastic improvements in hp/displacement and consumption/hp, whereas consumption/ displacement has changed very little. But then that last metric has less relevance, given the proliferation of down sized engines. The average engine size in 1975 was 300 cubic inches; it’s 170 cubic inches in 2020.

The growth of gas-electric hybrids is growing again, after a lull.

The growth of EVs and plug-in hybrids has of course accelerated strongly in the past few years. Fuel cell vehicles are still an extreme minority.

This chart shows the EV range has increased on average, now very close to 300 miles. That number seems a bit high to me, but EV sales are dominated by Tesla, and most of them do achieve that or greater range. The efficiency of EVs has been increasing too, and not by an insignificant amount.

Diesels are hanging in there, but with barely more than a 1% share of the market, and almost exclusively in pickups and truck SUVs.

4WD has grown from less than 10% to well over 50%. Now if we only had a statistic as to how often it actually is utilized.

This is just the tip of the iceberg, so help yourself to the rest of it here.