distinction.) Ni wound up being used as a slightly less familiar form of du, the singular second person pronoun, used to address people of lower social status. With the liberalization and radicalization of Swedish society in the 1950s and 1960s, these class distinctions became less important, and du became the standard, even in formal and official contexts. Though the reform was not an act of any centralized political decree, but rather the result of sweeping change in social attitudes, it was completed in just a few years, from the late 1960s to early 1970s. The use of ni as a polite form of address is sometimes encountered today in both the written and spoken language, particularly among older speakers. Geographic distribution Swedish is the sole official national language of Sweden, and one of two in Finland (alongside Finnish). As of 2006, it was the sole native language of 83% of Swedish residents. In 2007, around 5.5% (c. 290,000) of the population of Finland were native speakers of Swedish, partially due to a decline following the Russian annexation of Finland after the Finnish War 1808–1809. The Finland Swedish minority is concentrated in the coastal areas and archipelagos of southern and western Finland. In some of these areas, Swedish is the predominant language; in 19 municipalities, 16 of which are located in Åland, Swedish is the sole official language. Åland county is an autonomous region of Finland. According to a rough estimation, as of 2010 there were up to 300,000 Swedish-speakers living outside Sweden and Finland. The largest populations were in the United States (up to 100,000), the UK, Spain and Germany (c. 30,000 each) and a large proportion of the remaining 100,000 in the Scandinavian countries, France, Switzerland, Belgium, the Netherlands, Canada and Australia. Over 3 million people speak Swedish as a second language, with about 2,410,000 of those in Finland. According to a survey by the European Commission, 44% of respondents from Finland who did not have Swedish as a native language considered themselves to be proficient enough in Swedish to hold a conversation. Due to the close relation between the Scandinavian languages, a considerable proportion of speakers of Danish and especially Norwegian are able to understand Swedish. There is considerable migration between the Nordic countries, but owing to the similarity between the cultures and languages (with the exception of Finnish), expatriates generally assimilate quickly and do not stand out