Includes four major pollutants
- Nitrogen Dioxide
- Sulphur Dioxide
- Carbon Monoxide
- Ozone
- **City: San Diego
- **Mean : The arithmetic mean of concentration of NO2, O3, SO2 and O3 within a given Month of the year
- UNIVARIATE The arithmetic mean of concentration of NO2within a given Month of the year
- MULTIVARIATE The arithmetic mean of concentration of NO2, O3, SO2 and O3 within a given Month of the year