Are Americans embracing smaller homes? The U.S. Census Bureau recently reported that the average size of new-construction homes actually declined slightly, from an all-time high of 2,467 square feet in 2015 to 2,422. "New Houses Get Smaller," the Wall Street Journal declared, spotting a trend; "U.S. Homes Are Finally Shrinking," another piece at Bloomberg concluded. Many other commentators jumped on the news to argue that at last the U.S. was giving up its addiction to living large.

As exciting as it seemed, McMansions are not exactly being absorbed by the "tiny house movement." The statistic that started the fervor is actually a rather poor proxy for grasping long-term trends in housing because it fails to capture changes in household size, among other shortcomings. If the average home doubles in size, but the average number of inhabitants triples during that same period, then these "bigger" homes actually would feel smaller to the people living in them. Each person has less space to themselves.

Last year, three researchers — Maria Cecilia P. Moura, Steven J. Smith and David B. Belzer — published a paper that clarifies much of the confusion over this subject by measuring the amount of floor space per capita: How much room, in other words, does the average American have at any given time? They mined data from federal housing surveys and other sources to construct a data set that went back to 1891.

The results are illuminating. First, they found that the average size of the American home — not just new homes, but all homes — has remained remarkably constant over the past 120 years. Between 1890 and 1919, the average detached single-family home was 2,232 square feet in size. In the 1920s, that number went down to 2,046 square feet.

In the Great Depression of the 1930s, the number dropped further to 1,944 square feet, and then dropped again in the 1940s to 1,669, thanks to the construction of numerous modest suburban homes. And then the average size of the American home gradually increased, from 1,773 square feet in the 1950s to 2,673 in the 2000s.

In other words, between the 1890s and the first decade of the 21st century, single-family homes increased in size by approximately 20 percent. That's an increase, for sure, but it's hardly a dramatic one. And if you add in the other kinds of housing that people occupy — multifamily units like apartments and condos — the increase in the average size of all housing units is even more modest.

Indeed, if you look at 120 years of housing history, what jumps out is how little the size of our dwellings has changed.

What has changed, however, is the number of people living in each housing unit. Put differently, it's the square-feet-per-capita figure that should command our attention, not the size of the house itself. And here you can see a steady, but dramatic, change.

Since the 1890s, household size has declined dramatically. As a consequence, the average square feet of living space per capita has grown. In the 1890s, Americans had an average of 400 square feet of residential space per person. But by the early 21st century, that figure had doubled to 800 square feet. This is a change worth noting, and it's one that has progressed at a relatively steady rate, with little fluctuation.

The debate and discussion over the size of American residences is in many ways a misguided one. A 3,000-square-foot home that houses five people is not fundamentally different from a 600-square-foot studio apartment housing one person.

The big historical trend has been about per-capita floor space growing, not overall house size shrinking. If the trends of the past century continue, it'll be more still in the decades to come. Americans have more space than ever before — though what they are doing with it is a different question altogether.

Stephen Mihm is an associate professor of history at the University of Georgia and a contributor to Bloomberg View.