YEAR	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Annual 24-hr Avg.
1990	17606	18135	18251	17671	16783	17590	17146	17792	16798	16436	17030	15519	17222
1991	16327	17345	16970	18569	17398	17740	18576	24501	29632	28728	28240	27786	21836
1992	29175	23893	19272	20298	18317	19904	18584	18209	20650	20591	19073	18681	20598
1993	18026	20499	20514	22170	20378	20857	19578	19598	21128	20302	19789	20371	20258
1994	19959	21598	22081	22149	20726	21587	19237	20752	22304	22034	21100	20010	21117
1995	20546	22216	22793	23268	21540	22196	20158	21477	22705	23121	21363	20161	21795
1996	20448	22321	22202	23363	19201	19350	18888	20416	22299	21759	21253	19149	20887
1997	19405	21692	21451	22892	21342	20788	19020	20290	22514	22329	21353	19631	21059
1998	19271	21864	21797	23159	20727	21107	19252	20495	21974	21952	20356	19475	20952
1999	19518	21272	21501	22603	20858	21076	19194	20618	21763	22083	20663	19347	20875
2000	19616	23587	23405	22618	20823	21599	19762	20100	21703	22145	20723	19623	21309
2001	19436	21493	21412	22482	20039	19923	18606	19861	20887	21145	20062	18231	20298
2002	18780	20359	19571	21499	19520	18681	17578	18687	20228	20793	19174	18294	19430
2003	18954	20243	19242	21098	19460	19524	18371	18763	21269	21282	18985	18583	19648
2004	18620	20283	20764	21681	19252	18921	17969	19302	21500	20891	19922	18493	19800
2005	19075	20655	20571	21478	19333	19284	18133	20635		21144	19881	18428
2006	18851	21100	20702	21278	20579	19203	18186	22243			21652	18150
2007	19246	21151	20827	21602	21606		18881	19811	17576	22467	20524	18429
2008	17927	20914	19800	21612	19743	18224	17474	18195		19591	18182	17205
2009	16922	19597	18919	20666	18317	17620	17548

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