Year PM2.5 PM10 O3 NO2
2000 30.5 17.7 21.4
2001 27.9 30.0 18.4
2002 29.1 19.2 20.9
2003 41.3 58.2 27.2
2004 25.5 20.2 19.7
2005 32.8 23.6 20.3
2006 13.4 38.2 45.2 17.7
2007 4.2 28.4 21.0 19.4
2008 7.5 22.9 15.4 11.8
2009 7.4 23.9 15.0 14.9
2010 9.6 24.9 16.7 13.1
2011 13.9 30.2 14.7 11.9
2012 11.0 21.5 14.2 8.0