any one country, limits in place until the Immigration Act of 1990. Quotas by country under successive laws Listed below are historical quotas on immigration from the Eastern Hemisphere, by country, as applied in given fiscal years ending June 30, calculated according to successive immigration laws and revisions from the Emergency Quota Act of 1921 to the final quota year of 1965. The 1922 and 1925 systems based on dated census records of the foreign-born population were intended as temporary measures; the full National Origins Formula based on the 1920 Census of the U.S. population took effect on July 1, 1929. Relaxation and abolition The Immigration and Nationality Act of 1952 retained but relaxed the National Origins Formula. It modified the ratios to be based on the 1920 census and eliminated racial restrictions, but retained restrictions by national origin. President Harry Truman vetoed it because of its continued use of national quotas, but the Act was passed over his veto. The quotas were in addition to 600,000 refugees admitted from Europe after World War II. The National Origins Formula was abolished by the Immigration and Nationality Act of 1965, which marked a significant change in American immigration policy. It replaced the system with two quotas for the Western and Eastern hemispheres. See also Dillingham Commission Immigration policy Notes Further reading Michael Lemay and Elliott Robert Barkan, eds., U.S. Immigration and Naturalization Laws and Issues: A Documentary History Greenwood Press, 1999 John Lescott-Leszczynski, The History of U.S. Ethnic Policy and Its Impact on European Ethnics Westview Press, 1984 Anti-Asian sentiment in the United States History of immigration to the United States Immigration to the United States United States federal immigration and nationality legislation