CREATE TABLE table_204_553 (id DECIMAL, "outcome" TEXT, "no." DECIMAL, "date" TEXT, "tournament" TEXT, "surface" TEXT, "partner" TEXT, "opponents in the final" TEXT, "score in the final" TEXT)

where was the only tournament in 1991 held ?
SELECT "tournament" FROM table_204_553 WHERE "date" = 1991
SELECT "tournament" FROM "table_204_553" WHERE "date" = 1991