This information comes fromRand McNally....Atlas of American History pg. 31.
I don't know if you have access to this information, but it is the chart on that page titled Area of Selected Lands Added to the United States, 1803-1867.
The first territory that the United States acquired that was not immediately adjacent to the rest of the country was Alaska. Many Americans criticized Secretary of State William Seward for buying a wasteland of ice and snow, which they called "Seward's icebox" or "Seward's folly." The names from an Aleut word meaning "great land." According to the graph on page 31, of the Atlas, how does the size of the region compare with other territories that the United States acquired in the 1800s?