Figure 9: Traffic volume (Vehicle Miles Traveled) collected hourly graphed with PM2.5 hourly (Μg/m3) and CO hourly (ppm) data in the evenings (7pm to 12am). Traffic data was available in January for 2012. Particulate data was available each January from 2008 to 2010. CO data was available each January from 2000 to 2010. Each were averaged over all years available.