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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Summary Figure 3 - National Transportation Emissions Trend Index: 1970-97

Monday, September 10, 2012

Summary Figure 3 - National Transportation Emissions Trend Index: 1970-97

Summary Figure 3: National Transportation Emissions Trend Index: 1970-97. If you are a user with disability and cannot view this image, please call 800-853-1351 or email answers@bts.gov for further assistance.

NOTE: In estimating criteria and related pollutant emissions for 1997, the Environmental Protection Agency (EPA) made adjustments to prior years. For onroad mobile sources, EPA revised 1996 data. For nonroad mobile sources, EPA revised some estimates back to 1970. The figure reflects those changes and supercedes the similar figure 4-8 in Transportation Statistics Annual Report 1998.

SOURCE: See figure 5-8 in chapter 5.