years for females). Following the dissolution of the Soviet Union, Ukraine's population hit a peak of roughly 52 million in 1993. However, due to its death rate exceeding its birth rate, mass emigration, poor living conditions, and low-quality health care, the total population decreased by 6.6 million, or 12.8% from the same year to 2014. According to the 2001 census, ethnic Ukrainians made up roughly 78% of the population, while Russians were the largest minority, at some 17.3% of the population. Small minority populations included: Belarusians (0.6%), Moldovans (0.5%), Crimean Tatars (0.5%), Bulgarians (0.4%), Hungarians (0.3%), Romanians (0.3%), Poles (0.3%), Jews (0.3%), Armenians (0.2%), Greeks (0.2%) and Tatars (0.2%). It was also estimated that there were about 10–40,000 Koreans in Ukraine, who lived mostly in the south of the country, belonging to the historical Koryo-saram group. Outside the former Soviet Union, the largest source of incoming immigrants in Ukraine's post-independence period was from four Asian countries, namely China, India, Pakistan and Afghanistan. In the late 2010s 1.4 million Ukrainians were internally displaced due to the war in Donbas, and in early 2022 over 4.1 million fled the country in the aftermath of the Russian invasion. Language According to Ukraine's constitution, the state language is Ukrainian. Russian is widely spoken in the country, especially in eastern and southern Ukraine. Most native Ukrainian speakers know Russian as a second language. Russian was the de facto dominant language of the Soviet Union but Ukrainian also held official status in the republic, and in the schools of the Ukrainian SSR, learning Ukrainian was mandatory. Effective in August 2012, a new law on regional languages entitled any local language spoken by at least a 10 percent minority be declared official within that area. Within weeks, Russian was declared a regional language of several southern and eastern oblasts (provinces) and cities. Russian could then be used in the administrative office work and documents of those places. On 23 February 2014, following the Revolution of Dignity, the Ukrainian Parliament voted to repeal the law on regional languages, making Ukrainian the sole state language at all levels; however, the repeal was not signed by acting President Turchynov or by President Poroshenko. In February 2019, the law allowing for official use of regional languages was found unconstitutional. According to the Council of Europe, this act fails to achieve fair protection of the linguistic rights of minorities. Ukrainian is the