The percentage of single-person households in the US has been steadily increasing since the 1960's (though the rate of increase has moderated in recent decades). As of last year (2018), 28% of Americans lived alone, according to the US Census Bureau. So about 1 in 4 households. This is in comparison to 13.1% of households in 1960.

Here is a chart from a recent WSJ article on the topic:

Not surprisingly, this is changing how marketers target households. Affluent, single-person households in urban areas have proven to be a boon to product makers because they tend to spend more per person and they tend to value time > money. Of course, this phenomenon also has implications for those of us who work as city builders.

For more historical household tables from the US Census Bureau, click here.