Environmental Performance Methodology

Comparison Methodology

Environmental performance is calculated by comparing local air quality metrics to established national averages:

• AQI: National average AQI of 35 is used as the baseline. Local AQI below 35 is "Better," between 35-50 is "Similar," and above 50 is "Worse."
• PM2.5: National average of 10 µg/m³. Local values below 10 µg/m³ are "Better," between 10-15 µg/m³ are "Similar," and above 15 µg/m³ are "Worse."
• PM10: National average of 20 µg/m³. Local values below 20 µg/m³ are "Better," between 20-30 µg/m³ are "Similar," and above 30 µg/m³ are "Worse."

Data Sources

National averages are derived from EPA monitoring data across all US monitoring stations. Local data comes from the nearest monitoring station to each ZIP code.

Limitations

• National averages may vary by season and year
• Local conditions can vary significantly within a ZIP code
• Comparison is based on current readings, not annual averages