The table compares the percentage distribution of US households by size in 1790, 1890 and 1990, together with the average number of people per household.
Overall, there was a clear and steady shift towards smaller household sizes over the period, reflected in the sharp rise in one- and two-person households and a substantial fall in larger family units.
In 1790, large households were common, with 35.8% consisting of seven people, the highest proportion among all categories. Households of four to six members also accounted for a significant share, while only 3.7% lived alone. By 1890, the distribution became more balanced: six- and seven-person households declined, whereas three- and four-person households increased, and the average household size fell slightly from 5.4 to 4.9.
By 1990, the pattern had changed dramatically. Two-person households became the most prevalent at 32.2%, followed by one-person homes at 24.6%. In contrast, households with six or seven people together accounted for less than 4% combined. Consequently, the average household size dropped sharply to 2.6, highlighting a long-term trend toward smaller living arrangements.