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本章主要介绍了美国1980年人口普查所反映的人口增长、分布和迁移特点及其原因。
World War II
Florida
Texas
California
San Diego
San Antonio
Cleveland
Washington. D. C.

13，16，30，45秒处有破折号


Americans have been migrating south and west in larger number since World War II, and the pattern still prevails. Three sun-belt states -- Florida, Texas and California -- together had nearly 10 million more people in 1980 than a decade earlier. Among large cities, San Diego moved from 14th to 8th and San Antonio from 15th to 10th -- with Cleveland and Washington. D. C. dropping out of the top ten. Not all that shift can be attributed to the movement out of the snow belt, census officials say, Nonstop waves of immigrants played a role, too -- and so did bigger crops of babies as yesterday's 'baby boom' generation reached its child bearing years.
第二次世界大战以来，美国人口大量向南部和西部地区迁移，而且这种趋势如今仍然盛行。 佛罗里达、得克萨斯和加利福尼亚这三个阳光地带的州，1980年的人口比前10年增加了近1 000万。在大城市排行榜上，圣地亚哥从第14位上升到第8位，圣安东尼奥从第15位升到第10位，而克利夫兰和华盛顿特区则被挤出了前10位。 人口普查官员说，并非所有这些人口迁移都是为了离开寒冷地带。不断涌入的移民，还有往昔"生育高峰"时期出生的一代也已到了生育年龄，生育了大批婴儿，这些都发挥着作用。