Year
|
NH3
|
NOX
|
PM2.5
|
SO2
|
1990
|
0.1
|
2.1
|
6.5
|
3.0
|
1991
|
0.1
|
2.0
|
3.2
|
2.9
|
1992
|
0.1
|
2.0
|
2.7
|
2.9
|
1993
|
0.1
|
2.1
|
2.5
|
3.1
|
1994
|
0.1
|
2.1
|
2.3
|
3.0
|
1995
|
0.1
|
2.1
|
1.6
|
3.0
|
1996
|
0.1
|
2.0
|
1.3
|
2.9
|
1997
|
0.1
|
2.0
|
1.4
|
2.8
|
1998
|
0.1
|
2.1
|
1.5
|
3.0
|
1999
|
0.1
|
2.0
|
1.3
|
2.9
|
2000
|
0.1
|
2.0
|
1.2
|
2.8
|
2001
|
0.1
|
1.9
|
1.0
|
2.8
|
2002
|
0.1
|
1.9
|
1.0
|
2.7
|
2003
|
0.1
|
1.3
|
0.9
|
1.8
|
2004
|
0.1
|
1.4
|
0.9
|
1.9
|
2005
|
0.1
|
1.5
|
0.9
|
2.0
|
2006
|
0.1
|
1.4
|
1.1
|
2.0
|
2007
|
0.1
|
1.4
|
1.0
|
1.9
|
2008
|
0.1
|
1.3
|
1.4
|
1.7
|
2009
|
0.1
|
1.2
|
1.1
|
1.6
|
2010
|
0.1
|
1.2
|
1.2
|
1.6
|
2011
|
0.1
|
1.1
|
1.1
|
1.4
|
2012
|
0.1
|
1.1
|
1.1
|
1.4
|
2013
|
0.1
|
1.1
|
0.8
|
1.3
|
2014
|
0.1
|
1.0
|
0.8
|
1.2
|
2015
|
0.1
|
1.0
|
0.9
|
1.2
|
2016
|
0.1
|
1.0
|
0.9
|
1.2
|
2017
|
0.1
|
1.0
|
0.9
|
1.2
|
2018
|
0.1
|
1.0
|
0.9
|
1.2
|