In this part, we report on the state of bilingualism of the inhabitants of a number of countries. National censuses, or large language surveys, offer data from which estimates of bilingualism can be worked out based either on language use, or language knowledge (potential bilinguals are also included here), or both.

I have always been fascinated by the state of bilingualism in the United States maybe because I lived there for many years and one of its eminent scholars, Einar Haugen, himself a Norwegian-English bilingual, became a close colleague and friend. As stated above, the US Census Bureau does not keep track of bilingualism as such, but ever since 1980, and annually since 2000 with the American Community Survey (ACS), three language questions are asked (see the preceding part), and they allow us to work out, to a large extent, who is bilingual and where bilinguals are situated.

The 2018 ACS found that 67.3 million inhabitants (native-born, legal immigrants, and illegal immigrants) spoke a language other than English at home (Zeigler and Camarota 2019). Among those people, some 63 million also knew and used English and hence were bilingual. This represents 20.55% of the population. If we add to this number bilingual children under 5 (not covered by the survey) as well as people who use a second or third language in their everyday lives but only English at home, then probably close to 23% of the population can be considered bilingual.