National Trends in Sulfur_Dioxide Concentrations in 2000 - 2014
| Year |
Mean |
Number of Trend Sites |
10th Percentile |
90th Percentile |
| 2000 |
76.8942477876106 |
226 |
12.4 |
165 |
| 2001 |
76.6178466076696 |
226 |
13.4 |
159 |
| 2002 |
69.4612831858407 |
226 |
12 |
139 |
| 2003 |
70.8329646017699 |
226 |
12 |
153 |
| 2004 |
67.698598820059 |
226 |
11 |
143 |
| 2005 |
68.3947640117994 |
226 |
11 |
140 |
| 2006 |
65.1421828908554 |
226 |
11 |
138 |
| 2007 |
61.7082595870206 |
226 |
10.5 |
137 |
| 2008 |
55.9137168141593 |
226 |
9 |
133 |
| 2009 |
47.648820058997 |
226 |
8 |
113 |
| 2010 |
43.9484513274336 |
226 |
7 |
101 |
| 2011 |
36.8236725663717 |
226 |
6 |
80.5 |
| 2012 |
35.1387168141592 |
226 |
5 |
80 |
| 2013 |
29.6674041297935 |
226 |
4.3 |
63 |
| 2014 |
28.979203539823 |
226 |
4.9 |
60 |