Year,Jan.,Feb.,Mar.,Apr.,May.,Jun.,Jul.,Aug.,Sep.,Oct.,Nov.,Dec.,24-Hour Annual Avg.,
1990,11092,11836,12605,13409,18774,20520,14441,13957,13158,13146,12397,12397,13986,
1991,11220,12341,12980,13797,13597,13982,14246,14033,13813,13729,12926,12381,13257,
1992,11267,12394,20800,21535,21313,22067,22508,15474,15596,15176,14265,13803,17243,
1993,12317,13769,14657,15584,15825,16368,15782,15697,15253,15249,14195,14446,14933,
1994,13987,14243,15947,16219,16561,16833,15888,16140,16240,16381,14966,14395,15657,
1995,14921,15800,16242,16907,17014,16945,16636,16830,17539,16425,15496,14662,16285,
1996,14466,15523,16458,18016,16662,16709,16559,16738,17033,16971,16152,14674,16330,
1997,14754,16168,16588,16870,17392,17744,17319,17388,17591,17678,17055,16466,16918,
1998,15940,17320,18117,18735,18629,18738,18054,18351,18056,18394,17534,16064,17828,
1999,15938,,,,,20239,19483,19516,19322,19720,18587,17803,,
2000,17800,18965,19620,20545,20269,20530,19620,19801,19729,19721,18561,18047,19434,
2001,17517,18846,19759,21008,21937,21015,,,,,,,,
2002,,,,,,,,,,,,,,
2003,,,,,,,,,,,,,,
2004,,,,,,,,,20191,19516,18837,18484,,
2005,17396,19415,20113,20694,21377,21529,20124,20443,19676,19780,20977,,,
2006,18623,20423,20465,23098,23103,24144,23872,23543,21797,20392,20560,17699,21477,
2007,17619,19846,18857,20106,20517,,,19892,19259,19266,18341,16230,,
2008,,,16663,17823,17942,18218,,,16924,16653,15580,14972,,
2009,15044,16350,15930,,,,,15153,15726,15504,14820,14343,,
2010,14191,15803,16363,16947,16514,16627,16112,15842,,,14373,13972,,
2011,14273,14971,15272,16263,16330,,,,,,,14400,,
2012,14296,15501,15513,16534,16847,16145,15371,15884,16467,16109,15075,14399,15679,
2013,13475,15548,16431,17012,17050,16385,15803,16327,16459,16210,15336,13991,15836,
2014,14262,15879,17226,17974,17411,17174,16621,16577,17827,17601,15276,15718,16629,
2015,15656,17710,18766,20168,20184,20036,19360,19615,19777,19594,18239,17675,18898,
2016,17843,19533,20318,21878,21319,19390,18432,18709,18780,18349,17145,15890,18966,
2017,14739,17080,19188,20059,20056,20301,19336,19409,19452,19453,18527,17653,18771,
2018,17525,18605,19042,19786,19655,19750,18683,19297,19588,19691,18827,18087,19045,
2019,18092,19455,20731,21932,21209,20845,20281,20592,20701,20200,19271,18788,20175,
2020,18581,19976,17516,14392,17448,19032,18364,18569,19081,19525,17794,17498,18148,
2021,17859,18696,20885,21899,21407,20795,21386,20073,19842,19564,18927,18210,19962,
2022,17361,19440,19919,20623,20495,19771,19972,21565,21294,21443,19694,18639,20018,
2023,18554,19643,20187,21485,21579,20156,17563,19364,20207,20187,19602,18840,19781,
2024,17536,19270,20595, , , , , , , , , , ,