<P> A more complex quota plan, the National Origins Formula, replaced this "emergency" system under the Immigration Act of 1924 (Johnson - Reed Act). The reference census used was changed to that of 1890, which greatly reduced the number of Southern and Eastern European immigrants . An annual ceiling of 154,227 was set for the Eastern Hemisphere . Each country had a quota proportional to its population in the U.S. as of the 1890 census . </P> <P> In 1932 President Hoover and the State Department essentially shut down immigration during the Great Depression as immigration went from 236,000 in 1929 to 23,000 in 1933 . This was accompanied by voluntary repatriation to Europe and Mexico, and coerced repatriation and deportation of between 500,000 and 2 million Mexican Americans, mostly citizens, in the Mexican Repatriation . Total immigration in the decade of 1931 to 1940 was 528,000 averaging less than 53,000 a year . </P> <P> The Chinese exclusion laws were repealed in 1943 . The Luce - Celler Act of 1946 ended discrimination against Indian Americans and Filipinos, who were accorded the right to naturalization, and allowed a quota of 100 immigrants per year . </P> <P> The Immigration and Nationality Act of 1952 (the McCarran - Walter Act) revised the quotas again, basing them on the 1920 census . For the first time in American history, racial distinctions were omitted from the U.S. Code . As could be expected, most of the quota allocation went to immigrants from Ireland, the United Kingdom and Germany who already had relatives in the United States . The anti-subversive features of this law are still in force . </P>

Who signed the current immigration law into effect