iverson vs kobe shot efficiency over years

$ awk '{a=$9;f=$15;p=$25;t=(a+(f/2));e=(p/t);print e" "$1}' iv
1.00427 1996-97
1.05012 1997-98
0.994434 1998-99
0.97094 1999-00
1.018 2000-01
0.960245 2001-02
0.978723 2002-03
0.937833 2003-04
1.04244 2004-05
1.0628 2005-06
1.05622 2006-07
1.03311 2006-07
1.06667 2006-07
1.10692 2007-08
0.991501 2008-09
1.07163 2008-09
0.983051 2008-09
1.01099 2009-10
1.14953 2009-10
0.992857 2009-10

$ awk '{a=$9;f=$15;p=$25;t=(a+(f/2));e=(p/t);print e" "$1}' kob
1.07801 1996-97
1.06207 1997-98
1.07568 1998-99
1.07399 1999-00
1.08365 2000-01
1.06329 2001-02
1.0772 2002-03
1.08108 2003-04
1.09742 2004-05
1.09598 2005-06
1.13669 2006-07
1.12749 2007-08
1.10062 2008-09
1.07143 2009-10
1.07431 2010-11