CREATE TABLE table_32601 ("Year" FLOAT, "Sportsperson" CLOB, "Nationality" CLOB, "Team" CLOB, "Competition  ,  federation  ,  or league" CLOB, "Sport" CLOB)

How many years has the winner been a member of the National Football League?
SELECT AVG("Year") FROM table_32601 WHERE "Competition , federation , or league" = 'national football league'
SELECT AVG("Year") FROM "table_32601" WHERE "Competition , federation , or league" = 'national football league'