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2016 Air Quality Awareness Week

Air Quality Trends

May 3, 2017

You check the AQI every day to find out if today will be an unhealthy air quality day. But do you ever wonder if the number of unhealthy days is going up? -- going down? -- staying the same?

Here’s one way to look at it. For 35 metropolitan areas across the U.S., this graphic shows the total number of unhealthy days for ozone and fine particle pollution since the year 2000. The trend definitely shows improvement!

Fewer unhealthy air quality days means better health, longevity, and quality of life for all of us.

Bar Chart: Total Number of Days Reaching Unhealthy for Sensitive Groups or Above on the AQI
See separate graphics for ozone and PM2.5.

Learn more about air quality trends:

• For more on air quality trends in each of the 35 major cities, check out the 2016 Story Map for Ozone, 2016 Story Map for PM2.5 and the 2016 Combined Story Map.
• To see national and regional U.S. air quality trends, visit EPA's Air Trends site.

Moving to a different city? Planning a vacation? The AirCompare website has been redesigned, so now it’s even easier to compare air quality trends in different places. To see when and where air quality is better for you, check out the new
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