Notes: The shape of the age-sex pyramid of the immigrant population is very different from that of native-born population. There are several reasons for this. First, many migrants leave their home countries to find work abroad, so a high number of immigrants in the economically active ages of 20 to 54 is not uncommon. As can be seen in this age-sex pyramid, the majority of immigrants in 2011 were adults between the ages of 20 and 54. Second, in general, children rarely migrate by themselves and adult immigrants tend to migrate with few or no children. This helps explain the relatively small amount of people age 20 and younger. There is another reason, however: the children born in the United States to adult immigrants are considered native born and are not included in this age-sex pyramid. Third, people are less likely to migrate at older ages. In the foreign-born age-sex pyramid, there are clearly fewer people in the retirement-age groups (age 55 and over). This low number of older immigrants also has to do with many immigrants returning home for retirement and the death of older settled immigrants. All of these factors give the foreign-born age-sex pyramid its "diamond shape," making it significantly different from the native population pyramid.
There were about 40.4 million immigrants residing in the United States in 2011. Male-to-female ratio: 95.8. Click here to view the foreign born's male-to-female ratio between 1870 and 2011.
Source: US Census Bureau, American Community Survey, 2011.