What's the percentage of immigrants in 2004 in the country with 2.1% of the immigrants in 2006?
create table table_23619212_1 (_percentage_of_all_immigrants_2004 varchar, _percentage_of_all_immigrants_2006 varchar, PRIMARY KEY (_percentage_of_all_immigrants_2004))
select _percentage_of_all_immigrants_2004 from table_23619212_1 where _percentage_of_all_immigrants_2006 = "2.1%"