CREATE TABLE table_19680 ("Year" FLOAT, "Mens singles" CLOB, "Womens singles" CLOB, "Mens doubles" CLOB, "Womens doubles" CLOB, "Mixed doubles" CLOB)

What was the last year rni r hallgr msson dr fa har ard ttir won mixed doubles
SELECT MAX("Year") FROM table_19680 WHERE "Mixed doubles" = 'Árni Þór Hallgrímsson Drífa Harðardóttir'
SELECT MAX("Year") FROM "table_19680" WHERE "Mixed doubles" = 'Árni Þór Hallgrímsson Drífa Harðardóttir'