National Trends in PM25 Concentrations in 2000 - 2012
Year Mean Number of Trend Sites 10th Percentile 90th Percentile
2000 13.7818529164788 570 9.09317790520411 17.8491368784472
2001 13.4624980173979 570 9.2026140239382 17.2950151689991
2002 12.939410730687 570 8.84622123540044 16.3089474526369
2003 12.513438293471 570 8.27503415647425 16.0068835927121
2004 12.1318541027242 570 8.3809121892302 15.3823727422003
2005 13.1190657081541 570 8.22720773174817 16.804393822354
2006 11.777764108632 570 8.17013770424744 14.9411254201735
2007 12.1375047569358 570 8.09290856637519 15.4969319703182
2008 10.9422564494431 570 7.72150537634408 13.5061086013399
2009 9.8132502456435 570 7.19547291302505 12.115385353446
2010 10.0071059105761 570 6.88281638978837 12.9917754515599
2011 9.80506980793629 570 7.06691193285845 12.174328214477
2012 9.25242507976961 570 6.82593575007368 11.3584987371062