Out-of-control population growth and an endless exodus to the northn Net emigration is down to zero, if not negative, and the fertility rate will soon be lower than that of the United States.

那个“人口增长失控，大量人群北迁”的墨西哥也已不复存在——墨西哥的净移民数（出境移民减去入境移民的结果，译者注）不计负数已减少至零，其出生率也即将低于美国。

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It has a lower birth rate than the north and also has net emigration, particularly of the young and educated.

ECONOMIST: Southern Italy's ills

The Mexican baby boom of the 1950s coincided with lowish emigration, whereas the exodus to the United States kicked off in the 1980s, just as Mexico's birth rate was plummeting.

ECONOMIST: A falling birth rate, and what it means