The Baby Boom- Nearly 60,000 more people immigrated to the United States in 1965 than in 1964. Why then does the top line in the graph dip down between those years?

eo App- The Baby Boom
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76 Unit 5, Chapter 19 ... Section 2. The term baby boom refers to the years 1946 to. 1964 when the population of the United ... Interpreting Text and Visuals. 1.

Question 4.  Nearly 60,000 more people immigrated to the United States in 1965 than in 1964.  Why then does the top line in the graph dip down between those years?