National Trends in PM25 Concentrations in 2000 - 2014
| Year |
Mean |
Number of Trend Sites |
10th Percentile |
90th Percentile |
| 2000 |
13.4796118008357 |
505 |
8.81298356198245 |
17.7451302729529 |
| 2001 |
13.2269996869202 |
505 |
8.87638329914699 |
17.1555957796428 |
| 2002 |
12.789132463209 |
505 |
8.64138977259338 |
16.2360425206977 |
| 2003 |
12.3268835210155 |
505 |
7.94967357910906 |
16.0203154604017 |
| 2004 |
12.0009282321198 |
505 |
7.99971403420523 |
15.4638420936535 |
| 2005 |
12.8084840371833 |
505 |
7.84404170667629 |
16.6628261993383 |
| 2006 |
11.5868920680054 |
505 |
7.86237053619592 |
14.9383870967742 |
| 2007 |
11.8747181495927 |
505 |
7.58127976190476 |
15.4624600690733 |
| 2008 |
10.8359744040144 |
505 |
7.42651041666667 |
13.6112449017427 |
| 2009 |
9.76710741146692 |
505 |
6.93023690078038 |
12.1892208228725 |
| 2010 |
9.86319859388265 |
505 |
6.64833333333333 |
12.9978334245576 |
| 2011 |
9.73008062913105 |
505 |
6.69872728958102 |
12.1363663461723 |
| 2012 |
9.07228132208575 |
505 |
6.64199862637363 |
11.195685483871 |
| 2013 |
8.87596033044391 |
505 |
6.4259118893155 |
10.9882795698925 |
| 2014 |
8.77339917553809 |
505 |
6.07481134725883 |
11.0623192436039 |