CREATE TABLE table_61183 ("Nat." TEXT, "Name" TEXT, "Moving from" TEXT, "Type" TEXT, "Transfer window" TEXT, "Ends" FLOAT, "Transfer fee" TEXT, "Source" TEXT)

What is the average end year of the player from swe and a summer transfer window?
SELECT AVG("Ends") FROM table_61183 WHERE "Nat." = 'swe' AND "Transfer window" = 'summer'
SELECT AVG("Ends") FROM "table_61183" WHERE "Nat." = 'swe' AND "Transfer window" = 'summer'