CREATE TABLE table_40489 ("Tournament" TEXT, "2004" TEXT, "2005" TEXT, "2006" TEXT, "2007" TEXT)

What is the 2004 that has a of grand slam tournaments in2006 ?
SELECT "2004" FROM table_40489 WHERE "2006" = 'grand slam tournaments'
SELECT "2004" FROM "table_40489" WHERE "2006" = 'grand slam tournaments'