National Trends in Carbon_Monoxide Concentrations in 2000 - 2014
| Year |
Mean |
Number of Trend Sites |
10th Percentile |
90th Percentile |
| 2000 |
3.57127659574468 |
188 |
1.5 |
5.6 |
| 2001 |
3.34893617021276 |
188 |
1.5 |
5 |
| 2002 |
2.9845744680851 |
188 |
1.5 |
4.7 |
| 2003 |
2.78297872340425 |
188 |
1.4 |
4.3 |
| 2004 |
2.59521276595744 |
188 |
1.2 |
3.9 |
| 2005 |
2.32792553191489 |
188 |
1.2 |
3.6 |
| 2006 |
2.2281914893617 |
188 |
1.1 |
3.4 |
| 2007 |
1.95877659574468 |
188 |
1 |
3 |
| 2008 |
1.82021276595744 |
188 |
0.9 |
2.9 |
| 2009 |
1.7627659574468 |
188 |
0.9 |
2.6 |
| 2010 |
1.6127659574468 |
188 |
0.8 |
2.4 |
| 2011 |
1.59946808510638 |
188 |
0.9 |
2.4 |
| 2012 |
1.50611702127659 |
188 |
0.8 |
2.2 |
| 2013 |
1.46436170212766 |
188 |
0.7 |
2.4 |
| 2014 |
1.44574468085106 |
188 |
0.7 |
2.4 |