Troy Aikman 1989-2000
George Blanda (Also PK) 1949-1958, 1960-1975
Terry Bradshaw 1970-1983
Len Dawson 1957-1975
John Elway 1983-1998
Dan Fouts 1973-1987
Otto Graham 1946-1955
Bob Griese 1967-1980
Sonny Jurgensen 1957-1974
Jim Kelly 1986-1996
Bobby Layne 1948-1962
Dan Marino 1983-1999
Joe Montana 1979-1994
Warren Moon 1984-2000
Joe Namath 1965-1977
Bart Starr 1956-1971
Roger Staubach 1969-1979
Fran Tarkenton 1961-1978
Y.A. Tittle 1948-1964
Johnny Unitas 1956-1973
Norm Van Brocklin 1949-1960
Bob Waterfield 1945-1952
Steve Young 1985-1999
http://www.profootballhof.com/hof/po....CGyWTifC.dpuf
My guess is the stats are pushed down by the fact many are out of the league in a few years and the better ones last into their mid to late 30s some longer. Obviously those in the HOF are at the other end having gotten into the Hall by virtue of their longevity as well as great play.
Most good or better QBs retire on their own although a few get traded because of declining play. Johnny U was one who hung on too long.
Did you know there are only 5000 Snow Leopards in the wild now and they are confined to Central Asia? However, the effective global population (those likely to reproduce) is less than half that number.