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	Annual Toxics Summary Azusa FAQs Methyl Chloroform parts per billion

Year	Months Present	Minimum	Median	Mean	90th Percentile	Maximum	Standard Deviation	Number of Observations	Detection Limit
2025		*	*	*	*	*	*	0	*
2024		*	*	*	*	*	*	0	*
2023		*	*	*	*	*	*	0	*
2022		0.005	0.005	*	0.005	0.005	0.000	22	0.01
2021		0.005	0.005	*	0.005	0.005	0.000	24	0.01
2020		0.005	*	*	*	0.005	0.000	7	0.01
2019		0.005	0.005	0.005	0.005	0.005	0.000	30	0.01
2018		0.005	0.005	0.005	0.005	0.005	0.000	31	0.01
2017		0.005	0.005	0.005	0.005	0.005	0.000	29	0.01
2016		0.005	0.005	0.015	0.05	0.09	0.019	31	0.01
2015		0.005	0.005	0.011	0.03	0.03	0.010	30	0.01
2014		0.005	0.005	*	0.01	0.02	0.004	27	0.01
2013		0.005	0.005	0.006	0.01	0.01	0.002	31	0.01
2012		0.005	0.005	0.006	0.01	0.01	0.002	30	0.01
2011		0.005	0.005	0.007	0.01	0.01	0.003	30	0.01
2010		0.005	0.01	0.011	0.01	0.02	0.002	24	0.01
2009		0.01	0.01	0.012	0.02	0.02	0.004	31	0.01
2008		0.01	0.02	*	0.02	0.03	0.006	28	0.01
2007		0.01	0.02	0.029	0.02	0.28	0.052	27	0.01
2006		0.02	0.02	0.022	0.02	0.04	0.004	29	0.01
2005		0.02	0.02	0.027	0.03	0.10	0.015	29	0.01
2004		0.02	0.03	0.031	0.04	0.05	0.006	28	0.01
2003		0.03	0.04	0.041	0.05	0.07	0.009	28	0.01
2002		0.04	0.05	0.053	0.06	0.07	0.008	28	0.01
2001		0.04	0.07	*	0.09	0.13	0.020	26	0.01
2000		0.05	0.08	0.102	0.17	0.37	0.066	30	0.01
1999		0.07	*	*	*	0.07	1.43	1	0.01
1998		*	*	*	*	*	*	0	*
1997		*	*	*	*	*	*	0	*
1996		*	*	*	*	*	*	0	*
1995		*	*	*	*	*	*	0	*
1994		*	*	*	*	*	*	0	*
1993		*	*	*	*	*	*	0	*
1992		*	*	*	*	*	*	0	*
1991		*	*	*	*	*	*	0	*
1990		*	*	*	*	*	*	0	*
1989		0.35	*	*	*	4.2	1.43	7	0.01

	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.