It probably does not surprise anyone to see this table. This represents the number of players whose career in each year spanned 10 seasons. It does include AFL listed players who got dropped from their AFL side (or promoted to the SANFL side ), so it may be a bit artificial after 1990, and particularly 1997. I don't think it masks the fact that there are certainly not as many players who are long servers to the League. Or at least return to the SANFL after whatever absence may be - AFL, country, work etc
1990 46
1991 45
1992 46
1993 36
1994 29
1995 35
1996 36
1997 40
1998 34
1999 29
2000 36
2001 38
2002 38
2003 37
2004 35
2005 32
2006 31
2007 30
2008 39
2009 27
2010 34
2011 26
2012 28
2013 20
2014 22* as of Round 13