CREATE TABLE table_63684 ("Position" TEXT, "Appearances" FLOAT, "Goals" FLOAT, "First appearance" FLOAT, "Last appearance" FLOAT)

What is the average goals when the last appearance was before 1984, there were more than 17 appearances, the first appearance was before 1961 and the position was mf?
SELECT AVG("Goals") FROM table_63684 WHERE "Last appearance" < '1984' AND "Appearances" > '17' AND "First appearance" < '1961' AND "Position" = 'mf'
SELECT AVG("Goals") FROM "table_63684" WHERE "Appearances" > '17' AND "First appearance" < '1961' AND "Last appearance" < '1984' AND "Position" = 'mf'