YEAR	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Annual 24-hr Avg.
1990	23914	25259	26618	26206	26484	27638	27299	27385	26837	22546	23838	23123	25592
1991	20204	23896	23889	25017	24616	24770	25377	24645	23660	23881	22055	22595	23714
1992	21868	23048	23948	25788	25160	30591	24432	22302	22001	21768	20278	20407	23519
1993	19205	18587	18686	19487	19947	20646	22512	22490	22052	21000	20627	21065	20539
1994	20415	21200	21924	22256	21966	21970	19094	21830	22903	22408	21355	22405	21642
1995				24877	24609	26055	25180	25483	24640	23848	23515	23426
1996	22889	23946	24513	25393	25275	26290	24509	25388	24844	24462	24442	23568	24627
1997	23110	24629	24718	25974	25949	25959	24774	24940	24234	24076	23424	23222	24584
1998	22405	24007	24573	25908	25663	26933	25241	25490	25718	25549	22678	24152	24860
1999	23340	24167	24896	25828	25909	26770	25155	25501	25419	24889	23748	23562	24932
2000	23318	24686	25218	25833	25140	26191	24527	24643	24753	24359	23361	24048	24673
2001	23242	24702	25343	26167	26125	26331	25044	26108	25252	24409	22178	21673	24715
2002	21965	22860	22864	24979	25112	24781	24730	24573	23979	24132	22827	22568	23781
2003	22814	23519	23175	24506	24360	25273	24019	23963	24432	24183	22054	22843	23762
2004	21899	23041	24155	24785	23936	24761	23767	23745	24186	23695	23021	23180	23681
2005	22430	23552	24247	24788	24134	23871	22710	23787	23122	22713	22425	22982	23397
2006	22536	23527	23733	24044	24249	24281		24367	24237	23755	23122	22597
2007	22693	23492	24246	24652	24811	24854	23781	24786	23699	24017	23115	21967	23843
2008	21833	23333	22894	24355	24203	23473	22872

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