CREATE TABLE table_23619212_1 (_percentage_of_all_immigrants_2004 VARCHAR, _percentage_of_all_immigrants_2006 VARCHAR)

What's the percentage of immigrants in 2004 in the country with 2.1% of the immigrants in 2006?
SELECT _percentage_of_all_immigrants_2004 FROM table_23619212_1 WHERE _percentage_of_all_immigrants_2006 = "2.1%"
SELECT "_percentage_of_all_immigrants_2004" FROM "table_23619212_1" WHERE "2.1%" = "_percentage_of_all_immigrants_2006"