YEAR	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Annual 24-hr Avg.
1998		14859	16450	18191	20815		16739					12135
1999	15139	16197	17336	19283		23928	24536		22264	21483
2000			17437	20432				23932
2001	 
2002	 
2003	
2004	discontinued