Missouri air pollution stats

County	First data available	Last data available
Audrain Co	1997	1998
Boone Co	2002	2006
Buchanan Co	1997	2007
Cass Co	2000	2007
Cedar Co	1998	2007
Christian Co	1997	1997
Clay Co	1997	2007
Clinton Co	2004	2007
Cooper Co	2002	2006
Greene Co	1997	2007
Howell Co	1997	2001
Iron Co	1997	2004
Jackson Co	1997	2007
Jasper Co	1999	2007
Jefferson Co	1997	2007
Lincoln Co	1999	2007
Maries Co	2001	2004
Mercer Co	2002	2004
Monroe Co	1997	2007
Perry Co	2004	2007
Pike Co	2005	2007
Platte Co	1997	2005
St. Charles Co	1997	2007
St. Louis city	1997	2007
St. Louis Co	1997	2007
Ste. Genevieve Co	1997	2007
Stoddard Co	2001	2004
Taney Co	1997	2004