When it comes to covering pavement, it also starts at like 2008. Which is funny because I can guarantee you just from being around them that cars from the 70s were gigantic. Long hoods, big old protruding trunks.

I imagine the reason why the change is so small and why it's not quite a linear progression. There is that initial decrease again immediately post recession is just the shift in what's available for stock in the US.

The height of the SUV boom pre-recession, those cars were big. Like, we have CUVs now. Those are built on car chassis, which means they are about as long as a car is, about as wide as the car that they're based off of. For example, a Mazda CX6 is just a Mazda 6, but like, fatter. The popular SUVs of the late 2000s were like actually full-on SUVs built on heavy truck platforms. So we had things like the Hummer and of course the Escalade of the day which were gargantuan. At the same time, because those vehicles got like single digit miles per gallon, people tended to also have commuter cars, which were also a lot cheaper back then. We're talking like low 10,000s or less.

Post-recession though, like we did start seeing a lot more small cars again. For example Chevy brought in the Aveo and eventually the beat in the spark, Honda Fitts became bigger in terms of popularity, Ford brought over the Fiesta. And then gas went down again and because Americans have memories like a goldfish when it comes to gas, car sizes started growing again. When it happened again a few times during the 2010s and of course the big one during the pandemic and now cars had gotten more efficient in terms of their engine engineering and in terms of the prevalence of things like electric cars and hybrid units.

So that mid-sized CUV Is able to get better mile per gallon age or similar mile per gallon age to what someone driving around in a compact in 2007 might have gotten.

There's also a lot of unintended consequences from safety and computer designed aerodynamic models that have led to cars being shaped a very specific way with very thick A, B and C pillars which make the car door openings smaller which make the taller CUV options a little more appealing as well.

Also, just as an aside, I'm sure full-sized trucks wreck the curve because those have been getting bigger and bigger and bigger and it's kind of nuts how big they are and how, despite that, they're also less practical as work vehicles than ever before. Genuinely kind of stupid.