Last week we spoke about parking space dimensions. And my point was that these dimensions can dramatically change parking designs in new developments. In the comment section of this post, you’ll now find a number of examples of how these dimensions vary by city.

But the reality is that cars do keep getting bigger — at least in this part of the world. In the 1970s, SUVs and trucks made up less than a quarter of new car sales in the US. Today, this number is greater than 80%. It has become the standard kind of car.

So this week, let’s touch on why this has happened.

One argument might be that this was just what consumers inherently wanted. But there’s lots of evidence to suggest that this wasn’t really the case; it was instead encouraged by government policy.

One specific example is the creation of Corporate Average Fuel Economy standards (also known as CAFE). This was first introduced in the 1970s, but importantly, it was done with two different fuel economy standards: one for cars and one for light trucks.

Since the light truck standard was less onerous (see above chart), this created a strong incentive for car makers to just make and sell more light trucks. And curiously enough, that’s exactly what they did.

For much more on this topic, check out this comprehensive Vox article by David Zipper.