PM10-2.5 Distribution Statistics for 2011
Table 1. The following table shows summary statistics for PM10-2.5. The first column identifies the county and site name; the second column shows the number of valid samples; the third column shows the percentage of these samples for which negative concentration values were computed; the 4th through 7th columns show indicated percentile statistics, 25%, 50%, 75% and 98%; and the 8th column shows the arithmetic mean value.
| County / Site | No. Obs. | % neg. | 25th % | 50th % | 75th % | 98th % | Arith. Mean |
|---|---|---|---|---|---|---|---|
| Mecklenburg / Garinger | 116 | 0.0 | 3.70 | 5.50 | 7.52 | 12.37 | 5.83 |
| Mecklenburg / Montclaire 1 | 114 | 0.0 | 3.25 | 5.65 | 8.10 | 19.02 | 6.48 |
| Mecklenburg / Montclaire 2 | 57 | 0.0 | 3.00 | 5.70 | 7.80 | 21.32 | 6.76 |
| Durham / Durham | 110 | 0.9 | 3.93 | 5.60 | 6.88 | 11.84 | 5.74 |
| Wake / Millbrook | 115 | 0.0 | 3.64 | 5.29 | 6.73 | 11.61 | 5.34 |
| Catawba / Hickory* | 60 | 8.3 | 2.21 | 4.31 | 5.65 | 8.28 | 3.93 |
| Forsyth / Winston-Salem* | 381 | 2.8 | 2.90 | 5.28 | 7.35 | 11.61 | 5.31 |
| Guilford / Greensboro* | 52 | 30.8 | -1.09 | 1.59 | 3.78 | 8.28 | 1.73 |
| McDowell / Marion*# | 57 | 10.5 | 2.03 | 3.91 | 5.70 | 8.33 | 3.68 |
| Cumberland / Fayetteville* | 61 | 4.9 | 1.88 | 3.03 | 4.52 | 15.89 | 3.62 |
| Montgomery / Candor*# | 58 | 6.9 | 2.29 | 3.59 | 4.80 | 7.75 | 3.41 |
* Computed using nonmatching PM10 and PM2.5 monitor methods.
# Coverage is from March, 2011 through February, 2012.
Last Modified: Thu August 22 16:43:01 2013