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Select 8 Summary:	Choose Statistics, Years, & Areas	Frequently Asked Questions
•	Number of statistics times the number of years must equal 8 or less

Step 1:		Select Statistics
		Ozone 1-Hour		Ozone 8-Hour		PM2.5		PM10
		Days > Standard		Days > Standard		Est Days > Standard		Est Days > Standard
		National 1-Hour State 1-Hour 1-Hour Observations Maximum National 1-Year Estimated Expected Number of Exceedance Days National 3-Year Estimated Expected Number of Exceedance Days National Design Value State Designation Value Expected Peak Day Concentration Year Coverage		National 0.070 ppm Std National 0.075 ppm Std National 0.08 ppm Std State Standard 8-Hour Averages National 0.070 ppm Standard Maximum National 0.075 ppm and 0.08 ppm Standards Maximum State Maximum National 0.070 ppm Standard Design Value National 0.075 ppm Standard Design Value National 0.08 ppm Standard Design Value State Designation Value Expected Peak Day Concentration Year Coverage		National 24-Hour Annual Averages National State National Design Value State Designation Value 24-Hour Averages National Maximum State Maximum National 98th Percentile National Design Value Year Coverage		National 24-Hour State 24-Hour Annual Averages National State National 3-Year State 3-Year 24-Hour Averages National Maximum State Maximum Expected Peak Day Concentration Year Coverage

Step 2:		Select Years
		2023	2017	2011	2005	1999	1993	1987	1981	1975
		2022	2016	2010	2004	1998	1992	1986	1980	1974
		2021	2015	2009	2003	1997	1991	1985	1979	1973
		2020	2014	2008	2002	1996	1990	1984	1978
		2019	2013	2007	2001	1995	1989	1983	1977
		2018	2012	2006	2000	1994	1988	1982	1976

Step 3:		Select Areas
Map of California's Regions and Counties		Regions		California's Counties
		Greater Los Angeles		Alameda	Imperial	Mono	San	Solano
		Sacramento Valley		Alpine	Inyo	Monterey	Francisco	Sonoma
		San Diego		Amador	Kern	Napa	San Joaquin	Stanislaus
		San Francisco Bay		Butte	Kings	Nevada	San Luis	Sutter
		San Joaquin Valley		Calaveras	Lake	Orange	Obispo	Tehama
		Santa Barbara-		Colusa	Lassen	Placer	San Mateo	Trinity
		Ventura		Contra	Los Angeles	Plumas	Santa	Tulare
		Other Central State		Costa	Madera	Riverside	Barbara	Tuolumne
		Other Northern State		Del Norte	Marin	Sacramento	Santa Clara	Ventura
		Other Southern State		El Dorado	Mariposa	San Benito	Santa Cruz	Yolo
				Fresno	Mendocino	San	Shasta	Yuba
		Mexico		Glenn	Merced	Bernardino	Sierra
				Humboldt	Modoc	San Diego	Siskiyou

		Special Ozone 8-Hour Planning Areas
		Antelope Valley & W Mojave Desert	Sacramento Metropolitan Area	Sutter Buttes
		Central Mountain Counties	Sacramento Valley (remaining)	Tuscan Buttes
		Coachella Valley	San Luis Obispo (remaining)	Western Nevada County
		Eastern Kern County	South Coast
		E San Luis Obispo County	Southern Mountain Counties
Step 4:		Continue to Location Selection

Notes:			You may choose any combination of statistics and years such that the number of statistics chosen
			times the number of years chosen is 8 or less.
			The PM2.5 national statistics are based on the 2006 standards with the exception of the
			national maximum PM2.5 24-hour averages which are applicable to all national standards.
			Please click on each statistic for more informaton.
			Not all years are available for all pollutants.
			Not all pollutants and statistics are available for all regions, counties, or planning areas.
Go to:		Data Statistics Home Page