PM10-2.5 Distribution Statistics for 2012
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 4ththrough 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 | 114 | 0.0 | 3.97 | 5.75 | 7.48 | 13.15 | 6.10 |
| Mecklenburg / Montclaire 1 | 118 | 0.0 | 4.32 | 6.45 | 9.57 | 19.91 | 7.61 |
| Mecklenburg / Montclaire 2 | 61 | 0.0 | 3.70 | 5.20 | 9.30 | 21.56 | 7.11 |
| Durham / Durham | 112 | 0.0 | 3.91 | 5.56 | 6.86 | 15.67 | 5.91 |
| Wake / Millbrook | 119 | 0.0 | 3.79 | 5.33 | 7.04 | 12.45 | 5.66 |
| Catawba / Hickory* | 56 | 0.0 | 4.25 | 6.60 | 8.87 | 16.39 | 6.87 |
| Forsyth / Winston-Salem* | 338 | 3.8 | 3.21 | 4.88 | 6.62 | 12.11 | 4.99 |
| Guilford / Greensboro* | 50 | 10.0 | 2.79 | 5.22 | 8.28 | 13.68 | 5.42 |
| Martin / Jamesville* | 59 | 1.7 | 4.06 | 6.25 | 9.38 | 13.28 | 6.45 |
| Cumberland / Fayetteville* | 58 | 1.7 | 4.07 | 6.51 | 7.96 | 12.57 | 6.14 |
* Computed using nonmatching PM10 and PM2.5 monitor methods.