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Parity IV

Posted by Doug on August 18, 2006

Here are parts I, II, and III.

Let's check, for each season, the number of playoff teams that went back to the playoffs the next season:


Pair of years % repeaters
=============================
1970 ===> 1971 62.5
1971 ===> 1972 62.5
1972 ===> 1973 62.5
1973 ===> 1974 75.0
1974 ===> 1975 62.5
1975 ===> 1976 75.0
1976 ===> 1977 75.0
1977 ===> 1978 62.5 **
1978 ===> 1979 70.0
1979 ===> 1980 50.0
1980 ===> 1981 40.0
1981 ===> 1982 60.0 **
1982 ===> 1983 37.5 **
1983 ===> 1984 80.0
1984 ===> 1985 60.0
1985 ===> 1986 70.0
1986 ===> 1987 50.0
1987 ===> 1988 60.0
1988 ===> 1989 70.0
1989 ===> 1990 50.0 **
1990 ===> 1991 58.3
1991 ===> 1992 50.0
1992 ===> 1993 58.3
1993 ===> 1994 58.3
1994 ===> 1995 66.7
1995 ===> 1996 58.3
1996 ===> 1997 58.3
1997 ===> 1998 58.3
1998 ===> 1999 41.7
1999 ===> 2000 50.0
2000 ===> 2001 50.0
2001 ===> 2002 58.3
2002 ===> 2003 33.3
2003 ===> 2004 58.3
2004 ===> 2005 41.7

The asterisks indicate pairs of years where something about the playoff structure changed: 1978 was the introduction of the wildcard, 1990 was the second wildcard, and 1982 was the strike year in which the league decided to let 16 teams into the playoffs.

Here is another interesting look. For each year, this is the number of playoff teams from that year that had losing records the year before, the year after, or both:


# of playoff teams
with losing record
YR before after both
==============================
1970 3 1 1
1971 1 1 0
1972 2 2 1
1973 1 0 0
1974 1 0 0
1975 1 0 0
1976 1 0 0
1977 0 2 0
1978 1 2 0
1979 2 2 2
1980 3 6 2
1981 5 4 2
1982 6 5 1
1983 5 1 1
1984 1 1 0
1985 2 1 0
1986 1 4 1
1987 3 1 0
1988 4 2 0
1989 1 4 0
1990 1 1 0
1991 5 5 3
1992 2 1 0
1993 3 3 0
1994 3 2 2
1995 3 2 1
1996 3 5 1
1997 3 3 1
1998 4 4 2
1999 4 3 0
2000 4 5 2
2001 3 3 1
2002 5 8 3
2003 5 4 2
2004 4 4 1
2005 5

Don't forget to mentally adjust these numbers to account for the fact that there used to be eight playoff teams and there are now 12.

This entry was posted on Friday, August 18th, 2006 at 4:18 am and is filed under General, History. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.