Year
|
0-6 000 μg/m3.h
|
6 000-12 000 μg/m3.h
|
12 000-18 000 μg/m3.h
|
Greater than 18 000 μg/m3.h
|
1996
|
7.6
|
25.6
|
23.1
|
43.7
|
1997
|
9.8
|
29.7
|
30.7
|
29.9
|
1998
|
15.2
|
16
|
27.5
|
41.3
|
1999
|
4.5
|
17.1
|
40.3
|
38.1
|
2000
|
16.1
|
24.9
|
20
|
38.9
|
2001
|
10.6
|
23.6
|
20.7
|
45.1
|
2002
|
10.6
|
24
|
22.2
|
43.1
|
2003
|
8.5
|
13.6
|
12.6
|
65.2
|
2004
|
20.4
|
23.9
|
21.4
|
34.3
|
2005
|
12.7
|
16.6
|
25.2
|
45.4
|
2006
|
2.4
|
7.2
|
21.7
|
68.7
|
2007
|
23.7
|
25.3
|
18.8
|
32.2
|
2008
|
4.7
|
28.3
|
31.6
|
35.4
|
2009
|
20.1
|
33.6
|
24.1
|
22.3
|
2010
|
15.4
|
28.8
|
34.6
|
21.2
|
2011
|
12.6
|
26.8
|
42.4
|
18.2
|
2012
|
14.2
|
32.4
|
26.3
|
27.1
|
2013
|
19.8
|
36.6
|
22.9
|
20.7
|
2014
|
15.1
|
36.1
|
30.8
|
18
|
2015
|
21.1
|
25
|
23.7
|
30.2
|
2016
|
23.7
|
32.9
|
24.4
|
18.9
|
2017
|
24.1
|
31
|
18.8
|
26.1
|
2018
|
4.5
|
20
|
30.1
|
45.4
|
2019
|
14.4
|
23.8
|
24.9
|
37
|