1921 - Green Bay Packers
1925 - New York Giants
1930 - Detroit Lions (Portsmouth-OH Spartans)
1932 - Washington Redskins (Boston Braves)
1933 - Philadelphia Eagles and Pittsburgh Steelers (Pittsburgh Pirates)
1937 - St. Louis Rams (Cleveland Rams)
1950 - Cleveland Browns and San Francisco 49ers
1953 - Indianapolis Colts (Baltimore Colts)
1960 - Dallas Cowboys
1961 - Minnesota Vikings
1966 - Atlanta Falcons
1967 - New Orleans Saints
1970 - From the AFL/NFL merger: New England Patriots (Boston Patriots), Buffalo Bills, Cincinnati Bengals, Denver Broncos, Houston Oilers, Kansas City Chiefs, Miami Dolphins, New York Jets, Oakland Raiders and San Diego Chargers
1976 - Seattle Seahawks and Tampa Bay Buccaneers
1995 - Carolina Panthers and Jacksonville Jaguars
1997 - Baltimore Ravens
2002 - Houston Texans
