This land is still your land, pretty much the way it was for most Americans in 1940 when Woody Guthrie immortalized the gamut of the United States, from California to the New York Island and all the redwood forests, diamond deserts, wheat fields and golden valleys in between.

Except for one thing: There’s less of it. Officially, the nation’s land mass has been shrinking almost steadily ever since 1940.

According to the Census Bureau, the land area peaked that year at 3,554,608 square miles. By 1990, it had declined to 3,536,278 square miles. In 2000, a slight increase was recorded of about 1,200 square miles. But since then, the bureau estimates, this land has shrunk by about 5,500 square miles (a larger area than Connecticut and five times the size of Rhode Island), to 3,531,905.

Not to worry, though, the nation’s geographers say. Most of the decline is a result of improved satellite imagery and other mapping technology that can better distinguish land from water (like the gulf stream that Guthrie also glorified) and of more precise definitions of what constitutes each.