an increasing trend. Though since 2020, Covid 19 has started to cause the population to decline rapidly, with over 117,000 people reportedly dying from covid 19 in Poland by October 2022. Poland also saw a large number of Ukrainian Refugees move into Poland, with over 7.8 million people having crossed the border by October 2022 between Poland and Ukraine since the war began, of which 1.4 million have stayed in Poland. Declines within regions or ethnic groups of a country United States In spite of a growing population at a national level, some formerly large American municipalities have dramatically shrunk after the Second World War, and in particular during the 1950s–1970s, due to suburbanization, urban decay, race riots, high crime rates, deindustrialization and emigration from the Rust Belt to the Sun Belt. For instance, Detroit's population peaked at almost 2 million in 1953, and then declined to less than 700,000 by 2020. Other cities whose populations have dramatically shrunk since the 1950s include Baltimore, Buffalo, Cincinnati, Cleveland, Flint, Gary, New Orleans, St. Louis, Pittsburgh, Scranton, Youngstown and Wilmington (Delaware). In addition, the depopulation of the Great Plains, caused by a very high rate of rural flight from isolated agricultural counties, has been going on since the 1930s. In addition, starting from the 1950s, the United States has witnessed the phenomenon of the white flight or white exodus, the large-scale migration of people of various European ancestries from racially mixed urban regions to more racially homogeneous suburban or exurban regions. The term has more recently been applied to other migrations by whites, from older, inner suburbs to rural areas, as well as from the U.S. Northeast and Midwest to the warmer climate in the Southeast and Southwest. Migration of middle-class white populations was observed during the Civil rights movement in the 1950s and 1960s out of cities such as Cleveland, Detroit, Kansas City and Oakland, although racial segregation of public schools had ended there long before the Supreme Court of the United States' decision Brown v. Board of Education in 1954. In the 1970s, attempts to achieve effective desegregation (or "integration") using forced busing in some areas led to more families moving out of former areas. More recently, as of 2018, California had the largest ethnic/racial minority population in the United States; Non-Hispanic whites decreased from about 76.3 – 78% of the state's population in 1970 to 36.6%% in 2018 and