Table 1. Descriptive statistics.
| Index | Mean | Standard deviation | 25% quartile | Median | 75% quartile | Range |
|---|---|---|---|---|---|---|
| Pollution concentration | ||||||
| PM2.5 (μg/m3) | 55.9 | 49.5 | 25.0 | 41.0 | 71.0 | 481.0 |
| PM10 (μg/m3) | 93.3 | 66.2 | 53.0 | 77.0 | 114.0 | 12.0 |
| SO2 (μg/m3) | 30.7 | 28.9 | 8.0 | 16.0 | 48.0 | 148.0 |
| NO2 (μg/m3) | 40.8 | 14.0 | 30.0 | 39.0 | 48.0 | 98.0 |
| O3 (μg/m3) | 89.1 | 38.1 | 58.0 | 82.0 | 113.0 | 212.0 |
| Meteorology measures | ||||||
| Mean temperature (°C) | 7.0 | 13.8 | -5.8 | 9.2 | 19.5 | 52.6 |
| Average relative humidity (%) | 60.1 | 16.8 | 48.0 | 61.0 | 73.0 | 86.0 |
| Daily non-accidental death counts1 | ||||||
| Total | 32.0 | 6.5 | 27.0 | 32.0 | 36.0 | 39.0 |
| Women | 15.2 | 4.3 | 12.0 | 15.0 | 18.0 | 26.0 |
| Men | 16.8 | 4.4 | 14.0 | 17.0 | 20.0 | 28.0 |
| Junior high school and below | 24.1 | 5.6 | 20.0 | 24.0 | 28.0 | 35.0 |
| High school degree or above | 8.0 | 3.1 | 6.0 | 8.0 | 10.0 | 26.0 |
| Died in the hospital | 15.8 | 4.3 | 13.0 | 15.0 | 19.0 | 28.0 |
| Died outside the hospital | 16.2 | 4.5 | 13.0 | 16.0 | 19.0 | 28.0 |
| Daily circulatory diseases death counts2 (I00-I99) | ||||||
| Total | 18.1 | 4.7 | 15.0 | 18.0 | 21.0 | 33.0 |
| Women | 9.0 | 3.3 | 7.0 | 9.0 | 11.0 | 21.0 |
| Men | 9.1 | 3.1 | 7.0 | 9.0 | 11.0 | 21.0 |
| Junior high school and below | 14.2 | 4.2 | 11.0 | 14.0 | 17.0 | 29.0 |
| High school degree or above | 3.9 | 2.2 | 2.0 | 4.0 | 5.0 | 16.0 |
| Died in the hospital | 6.7 | 2.7 | 5.0 | 6.0 | 9.0 | 17.0 |
| Died outside the hospital | 11.4 | 3.7 | 9.0 | 11.0 | 14.0 | 24.0 |
1 people who died of all-nonaccidental causes
2 people who died of circulatory diseases.