YEAR,Jan,Feb,Mar,Apr,May,Jun,Jul,Aug,Sep,Oct,Nov,Dec,Annual 24-hr Avg.
2001,,,,,,,,,,15838,15393,13756
2002,12941,14638,16079,16225,17177,18914,19339,19969,17295,16674,15702,15075,16669
2003,13687,14303,15605,16030,17092,18849,19627,20259,17518,17052,15799,14238,16672
2004,13088,14214,16570,16893,16929,18427,19282,19365,17525,16812,16014,15291,16701
2005,13297,15207,16817,16643,16949,19014,19858,19609,17287,16597,16224,15191,16891
2006,14021,15248,16736,17412,17516,19433,19488,19767,18267,17393,16916,15762,17330
2007,14433,15723,17460,17504,17735,19409,20056,20525,18414,17676,17280,15093,17609
2008,13662,14838,16723,16552,17179,17999,19091