Is there any evidence that more people are attempting to live alone now than in the past (in the US)? Genuine question -- don't know the trend national trend.
Mean is a bit of a misleading number here since the distribution really is discrete - and there are a lot more 1 and 2 person homes today than before, which is contributing to the lower average.
Could this really just be showing that less people are marrying and having kids?
A further question would what is called a “household” (and how that has changed over time). Is a 4 room house with 4 renters room renter, 4 households or just one by the owner?
How does people owning multiple houses affect this number?
US census has a publication on how single-person households are skyrocketing.