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	Annual Statewide Toxics Summary Cobalt FAQs nanograms per cubic meter

Year	Months Present	Minimum	Median	Mean	90th Percentile	Maximum	Standard Deviation	Number of Observations	Detection Limit
2017		0.65	0.65	1.40	2.8	5.6	1.01	407	1.3
2016		0.65	0.65	0.69	0.65	3.0	0.21	424	1.3
2015		0.65	0.65	0.65	0.65	1.6	0.05	418	1.3
2014		0.8	0.8	1.03	1.8	4.5	0.66	398	1.6
2013		0.75	0.75	*	0.75	2.7	0.19	431	1.5
2012		0.75	0.75	0.92	0.75	4.0	0.53	444	1.5
2011		0.75	0.75	0.76	0.75	4.4	0.19	430	1.5
2010		0.75	0.75	0.76	0.75	2.0	0.09	440	1.5
2009		0.75	0.75	0.84	0.75	8.0	0.72	520	1.5
2008		*	*	*	*	*	*	0	*
2007		0.75	0.75	0.88	0.75	6.7	0.75	462	1.5
2006		*	*	*	*	*	*	0	*
2005		*	*	*	*	*	*	0	*
2004		*	*	*	*	*	*	0	*
2003		7.5	7.5	*	7.5	7.5	0.00	86	15
2002		7.5	7.5	7.77	7.5	20	0.61	491	15
2001		8	8	8.14	8	40	1.76	505	16
2000		8	8	8.12	8	26	1.16	472	16
1999		8	8	8.23	8	25	1.70	565	16
1998		8	8	8.02	8	18	0.42	561	16
1997		8	8	8.03	8	23	0.74	557	16
1996		8	8	8.00	8	8	0.00	595	16
1995		8	8	8.13	8	38	1.56	602	16
1994		8	8	8.15	8	33	1.46	585	16
1993		8	8	8.00	8	8	0.00	575	16
1992		8	8	8.01	8	17	0.38	554	16
1991		8	8	8.02	8	19	0.46	567	16
1990		8	8	*	8	17	0.51	309	16
1989		*	*	*	*	*	*	0	*

	Notes:	Values below the Limit of Detection (LoD) assumed to be ½ LoD. Means and risks shown only for years with data in all 12 months. "*" means there was insufficient or no data available to determine the value.