If we can find this thread a year from now, when we're ready to bet the 2012 prop, here are the recent yearly totals:
2003 — 29
2004 — 30
2005 — 68
2006 — 57
2007 — 93
2008 — 64
2009 — 30
2010 — 29
2011 — 39
2003 — 29
2004 — 30
2005 — 68
2006 — 57
2007 — 93
2008 — 64
2009 — 30
2010 — 29
2011 — 39