National Trends in Nitrogen_Dioxide Concentrations in 1980 - 2010
| Year |
Mean |
Number of Trend Sites |
10th Percentile |
90th Percentile |
| 1980 |
27.3413153404031 |
81 |
14.6386401578388 |
49.6280909990109 |
| 1981 |
26.9100805104878 |
81 |
14.0959079283887 |
49.0980597797588 |
| 1982 |
25.9012634162226 |
81 |
13.3723196881092 |
45.5803870677334 |
| 1983 |
25.1701286182289 |
81 |
12.5211889697983 |
45.4693097683305 |
| 1984 |
25.871545768085 |
81 |
13.7989420931847 |
44.0889257463639 |
| 1985 |
25.72183119915 |
81 |
14.0810087886893 |
42.8586983419946 |
| 1986 |
25.8440085284897 |
81 |
14.4789762340037 |
42.2671374649945 |
| 1987 |
25.3803904123763 |
81 |
14.9478767032676 |
41.9970631424376 |
| 1988 |
25.9785838301471 |
81 |
15.3869017632242 |
42.4260994953136 |
| 1989 |
25.1994660656622 |
81 |
13.646567586695 |
42.7639826422372 |
| 1990 |
23.9346148756502 |
81 |
14.4077167392072 |
40.1575003129045 |
| 1991 |
23.9009679411073 |
81 |
11.5659515043798 |
41.1153892431717 |
| 1992 |
22.9388473796769 |
81 |
13.0177158379591 |
38.9381606123193 |
| 1993 |
22.3956442748193 |
81 |
13.2510238496748 |
35.7398236501993 |
| 1994 |
23.4896905313426 |
81 |
12.7395017793594 |
41.1206440759433 |
| 1995 |
22.4381095216917 |
81 |
12.5970149253731 |
38.6732638482258 |
| 1996 |
21.9671376570415 |
81 |
12.244487287625 |
37.1240758994579 |
| 1997 |
20.8949825218113 |
81 |
11.968773419935 |
33.6668289713938 |
| 1998 |
20.8766969435848 |
81 |
11.612709685319 |
35.2829179331307 |
| 1999 |
21.579146178673 |
81 |
12.507339336376 |
37.2946364719905 |
| 2000 |
20.0337586291449 |
81 |
11.3298869920654 |
35.7072098824088 |
| 2001 |
19.9772999890108 |
81 |
11.4935828235576 |
33.9718779790276 |
| 2002 |
19.1936305157893 |
81 |
11.706364749082 |
32.8832580463015 |
| 2003 |
18.4568325413541 |
81 |
10.7924256951103 |
30.2796173657101 |
| 2004 |
17.0468029801076 |
81 |
10.4470399633574 |
27.2050557830815 |
| 2005 |
16.8712024721144 |
81 |
9.27395228087526 |
26.2947822035872 |
| 2006 |
15.9783399150987 |
81 |
9.70463624258564 |
25.8025508362411 |
| 2007 |
15.3598271697384 |
81 |
9.49170274170274 |
24.2207293666027 |
| 2008 |
14.5178827833054 |
81 |
7.74042087337307 |
23.0625528317836 |
| 2009 |
13.5637722013076 |
81 |
7.41901238539488 |
22.1260382809679 |
| 2010 |
13.0758441894904 |
81 |
7.23688064437393 |
20.4067345143862 |