Year	PM2.5	PM10	O3	NO2
2000		31.6	17.9	25.9
2001		30.1	30.5	22.3
2002		31.8	20.7	23.1
2003		43.1	54.9	31
2004		30.4	19.4	20.6
2005		33.2	22.7	21.4
2006	16	38	45.5	18.2
2007	10.5	31.8	21.8	20.7
2008	10.4	24.7	15.3	12.3
2009	8.6	24.9	16.1	14.3
2010	11.2	25.2	17.4	11.7
2011	13.1	30	16.1	11.8
2012	11.1	21.6	15.5	8.8
2013	8.2	20	16.2	8.9
2014	7.5	16.1	7.4	7.2
2015	7.1	18.7	29.5	8.7