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In 2012, resident foreigners made up 23.3% of the population. Most of these (64%) were from European Union or EFTA countries. Italians were the largest single group of foreigners with 15.6% of total foreign population. They were closely followed by Germans (15.2%), immigrants from Portugal (12.7%), France (5.6%), Serbia (5.3%), Turkey (3.8%), Spain (3.7%), and Austria (2%). Immigrants from Sri Lanka, most of them former Tamil refugees, were the largest group among people of Asian origin (6.3%). Additionally, the figures from 2012 show that 34.7% of the permanent resident population aged 15 or over in Switzerland, i.e. 2,335,000 persons, had an immigrant background. A third of this population (853,000) held Swiss citizenship. Four fifths of persons with an immigration background were themselves immigrants (first generation foreigners and native-born and naturalised Swiss citizens), whereas one fifth were born in Switzerland (second generation foreigners and native-born and naturalised Swiss citizens). In the 2000s, domestic and international institutions expressed concern about what they perceived as an increase in xenophobia, particularly in some political campaigns. In reply to one critical report the Federal Council noted that "racism unfortunately is present in Switzerland", but stated that the high proportion of foreign citizens in the country, as well as the generally unproblematic integration of foreigners", underlined Switzerland's openness.

What percentage of the population aged 15 and over were shown to have an immigrant background as of 2012?
34.7%