Year,Jan.,Feb.,Mar.,Apr.,May.,Jun.,Jul.,Aug.,Sep.,Oct.,Nov.,Dec.,24-Hour Annual Avg.,
1990,6223,6778,8237,8511,9034,10276,10438,10835,9068,8156,8018,6335,8501,
1991,6054,7193,8564,8410,9100,10319,10513,11356,9390,8844,8042,7753,8805,
1992,7458,8150,9012,9162,9682,11191,11378,11346,10232,9292,8562,7377,9432,
1993,6394,7259,8916,9373,9448,11865,12202,12404,10673,9896,8524,7840,9579,
1994,7745,8398,10285,10645,11244,12312,12566,12441,10474,9723,9017,8338,10277,
1995,7870,8469,9982,,,,,,,,9750,8670,,
1996,7719,8402,10321,10461,11351,12270,12722,13195,11360,10599,10184,8996,10632,
1997,8241,9154,10900,10801,11669,12781,13353,13557,11931,11233,11000,9916,11211,
1998,8821,9912,11257,11517,12350,13977,14278,14595,12811,12027,11820,10324,11974,
1999,9800,10385,12311,12275,12989,14391,14974,15376,13329,12486,12407,10817,12628,
2000,9648,10838,12539,12502,13212,14434,15104,15608,13285,12533,11821,10686,12684,
2001,9714,10642,12802,12687,13535,14575,14955,15463,13652,12695,12774,10475,12831,
2002,9982,11662,13411,12854,14104,15525,15585,16180,13788,13217,12556,12079,13412,
2003,10733,11284,12667,12917,14156,15314,15960,17105,14253,13570,12368,,,
2004,10317,9740,13541,13647,14085,15057,15838,15810,14010,13344,12968,11667,13335,
2005,10282,11735,13781,13431,13985,15455,16330,16504,13695,13205,13107,11784,13608,
2006,10825,11922,13994,14449,,16318,,17278,15761,14077,14797,12245,,
2007,11218,12319,14425,14323,14586,18095,,,14610,14036,13844,11721,,
2008,10102,11406,13699,13250,13556,14618,,14777,,,,10288,,
2009,10309,11542,13647,13784,14699,15271,,16482,14533,13740,,11410,,
2010,10762,10697,14199,13841,14494,,,16756,15040,14210,12778,12143,,
2011,11045,12053,13988,14041,14839,16568,,,,,,,,
2012,,,,,,,17010,17047,15059,14580,14116,12575,,
2013,10848,12029,14652,14375,15398,16754,17307,17358,14977,14605,13750,12098,14513,
2014,11493,12224,15102,15012,15742,17255,17739,17716,15747,15345,14265,13594,15103,
2015,12657,13889,16158,15655,16890,18570,19077,18481,16890,16212,15303,13661,16120,
2016,12720,14308,17024,16693,17944,19658,20236,19663,17922,17126,16575,13464,16945,
2017,11463,13743,17662,17993,18796,20373,20807,20195,18159,17756,16986,14871,17400,
2018,13701,14839,17622,18072,19098,21006,21531,21121,19179,18531,17975,15311,18166,
2019,14400,14218,18483,18745,19336,21004,21974,21030,19484,18760,17364,16056,18404,
2020,14153,15331,15515,11566,14734,19287,19955,20230,19746,18723,15877,15465,16715,
2021,14980,14863,19132,19464,20745,22630,22959,22580,20911,20077,19913,17459,19643,
2022,15234,17246,19986,20135,21389,22872,22559,22297,21071,20276,18885,16253,19850,
2023,15375,16380,19149,19804,21652,23643,23444,22591,20993,20347,19393,16894,19972,
2024,14332,17124,19173, , , , , , , , , , ,