Final answer:
Since 1940, there has been a significant increase in the percentage of Americans age 25 and older who have completed at least a high school education.
Explanation:
In the United States, since 1940, there has been a significant increase in the percentage of the population age 25 and older who have completed at least a high school education. This increase is evident from data showing a rise in educational attainment levels over the years. For example, as of 2010, about 8.5% of Americans age 25 or older had a high school degree, compared to 3.5% in 1940. Additionally, by 2010, about 28% of Americans had a four-year college degree.
Learn more about educational attainment trends in the U.S. here:
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