National Trends in PM10 Concentrations in 1990 - 2017

Year	Mean	Number of Trend Sites	10th Percentile	90th Percentile
1990	84.7786259541984	131	45	143
1991	85.9236641221374	131	47	134
1992	73.5038167938931	131	41	111
1993	74.1755725190839	131	41	113
1994	71.3905852417303	131	39	118
1995	73.0063613231552	131	38	125
1996	65.1450381679389	131	35	105
1997	65.2748091603053	131	38	107
1998	61.7277353689567	131	38	96
1999	68.1501272264631	131	37	113
2000	65.5572519083969	131	36	103
2001	62.9312977099236	131	36	97
2002	63.0572519083969	131	38	95
2003	64.7633587786259	131	32	116
2004	56.4351145038168	131	30	86
2005	58.8091603053435	131	33	93
2006	58.854961832061	131	35	93
2007	62.5356234096692	131	36	94
2008	56.972010178117	131	32	90
2009	51.7862595419847	131	27	82
2010	51.030534351145	131	29	77
2011	55.618320610687	131	28	80
2012	54.7633587786259	131	28	89
2013	59.4503816793893	131	25	107
2014	57.0839694656488	131	27	102
2015	53.1984732824427	131	29	78
2016	51.7099236641221	131	25	88
2017	56.3129770992366	131	25	94