Year,Jan.,Feb.,Mar.,Apr.,May.,Jun.,Jul.,Aug.,Sep.,Oct.,Nov.,Dec.,24-Hour Annual Avg.,
1990,14686,16758,17102,17620,17393,17572,16687,17061,18037,19218,18834,14850,17145,
1991,15306,16962,17076,17993,17919,17585,17408,17655,17791,18242,16774,16595,17275,
1992,16612,17791,18054,18673,17924,17968,17830,17840,19039,18886,17183,17512,17990,
1993,16200,17197,18948,18767,18342,18997,18140,18262,18410,18364,17530,17162,18029,
1994,16931,17585,19309,20327,18940,19272,18353,18366,18363,18364,17692,17091,18383,
1995,17136,18324,18553,18954,18943,19774,18028,,,,,,,
1996,,,,,,,,,,18520,17134,16742,,
1997,16777,18097,18225,19204,19378,18972,18129,18423,18433,18500,17682,16787,18217,
1998,16724,17821,18025,18659,18591,18775,17506,17588,18359,18618,17673,16966,17942,
1999,16802,17735,18495,18623,18853,18819,18127,18197,18371,18765,17774,17388,18162,
2000,17236,18087,18553,19041,18799,18917,17872,18378,18152,18383,17360,,,
2001,16966,17827,18445,18649,18651,17993,17021,17188,18005,18015,17289,15869,17660,
2002,16070,,,,,,,,15651,15828,16772,16289,,
2003,16662,16944,16484,17972,18037,17383,17171,17494,19950,18123,15898,16960,17423,
2004,16035,15929,16170,16733,15974,16706,17552,18058,18815,18102,16935,16356,16947,
2005,15495,16847,17593,18552,18272,18487,17092,18285,18711,17953,18161,18773,17852,
2006,16606,16744,,16306,16610,16808,15599,18979,19197,18163,17117,16036,,
2007,15441,16690,17500,18306,18809,17888,16554,18309,17664,17919,16474,15014,17214,
2008,15097,16219,,17361,17589,16838,16586,,17347,17365,15622,17612,,
2009,15019,16065,16496,18124,18096,17915,17151,16856,17050,16982,15926,15641,16777,
2010,15217,16402,16775,17609,16395,17074,16129,16657,16977,16831,17050,,,
2011,15729,16055,15973,17006,16627,16753,16382,15662,16124,16150,15023,14856,16028,
2012,15176,15709,15748,16963,16503,16227,15387,15934,15896,16062,15114,14582,15775,
2013,14012,15378,15674,16559,16455,16049,15268,15809,16027,16015,14906,14235,15532,
2014,14316,15262,15477,16371,16159,15733,15313,15784,16386,15778,14659,14400,15470,
2015,14530,15831,15767,16558,15962,15964,15192,15512,15891,15953,14702,14224,15507,
2016,14494,15544,15527,16582,16049,16126,15538,15732,15669,15649,14789,13945,15470,
2017,13557,15102,15339,16124,16044,15779,15096,15597,15502,15476,14728,13982,15194,
2018,14220,14844,14843,15866,15549,15326,15302,16816,16105,15637,14856,14159,15293,
2019,14142,14618,15356,16171,15738,15477,14885,15548,15927,15574,14746,14102,15190,
2020,14078,14953,13268,11196,13536,14397,14215,14657,14719,14413,13231,13041,13809,
2021,13472,13925,14865,15708,15618,15430,14776,15119,14993,15245,14289,13887,14777,
2022,13619,14598,14957,15480,15437,14934,14428,15182,15970,15847,14299,13682,14869,
2023,13973,14551,14507,15651,16352,15629,14995,15729,15743,16003,14937,14417,15207,
2024,14508,15915,16421, , , , , , , , , , ,