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Transportation Air Quality Selected Facts and Figures

Progress in Reducing Motor Vehicle Emissions

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Have We Made Progress in Reducing Motor Vehicle Emissions?

Air pollution emissions from motor vehicles have dropped considerably since 1970–VOC emissions are down 87 percent, NOx emissions are down 64 percent, PM10 emissions are down 37 percent, and CO emissions are down 86 percent. Since 1990, PM2.5 emissions are down 48 percent; however transportation carbon dioxide (CO2) emissions increased 16 percent. The reductions are due primarily to more stringent light-duty engine and fuel standards. These occurred at the same time as a 56 percent increase in population, 241 percent growth in gross domestic product, and 166 percent growth in VMT.

Percent Change in Motor Vehicle Emissions, Demographics, and Travel (1970–2013)

Title: Bar chart showing the percent change in motor vehicle emissions, demographics, and travel from 1970 to 2013 - Description: The bar chart shows air pollution emissions from motor vehicles have dropped considerably since 1970-VOC emissions are down 87 percent, NOx6 emissions are down 64 percent, PM-10 emissions are down 37 percent, and CO emissions are down 86 percent. Since 1990, PM-2.5 emissions are down 48 percent; however transportation CO2 emissions increased 16 percent. It also shows there was a 56 percent increase in population, 241 percent growth in gross domestic product, and 166 percent growth in VMT.

Notes: Figures for licensed tdrivers, tregistered vehicles and tVMT are from 2011. Data for PM2.5 and CO2 are from 1990.

Sources: Bureau of Transportation Statistics, National Transportation Statistics, Table 1-35, March 2014, http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_01_35.html

U.S. Census Bureau, Population Division, Table 1, Annual Estimates of the Resident Population for the United States, Regions, States, and Puerto Rico: April 1, 2010 to July 1, 2014 (NST-EST2014-01), http://www.census.gov/popest/data/national/totals/2014/NST-EST2014-alldata.html

U.S. Department of Commerce, Bureau of Economic Analysis, National Economic Accounts, May 2015, http://www.bea.gov/National/index.htm

U.S. Department of Labor, Bureau of Labor Statistics, The Employment Situation–February 2015, http://www.bls.gov/news.release/archives/empsit_03062015.pdf

Federal Highway Administration, Office of Highway Policy Information, Highway Statistics 2011, Chart DV- 1C, December 2012, http://www.fhwa.dot.gov/policyinformation/statistics/2011/dv1c.cfm

Federal Highway Administration Highway Statistics 2013, Public Road Mileage - VMT - Lane Miles 1920– 2013, Chart VMT-421C, http://www.fhwa.dot.gov/policyinformation/statistics/2013/vmt421c.cfm

U.S. Environmental Protection Agency, Clearinghouse for Inventories and Emissions Factors (CHIEF), Current Emission Trends Summaries, https://www.epa.gov/air-emissions-inventories/air-pollutant-emissions-trends-data

U.S. Environmental Protection Agency, Inventory of U.S. Greenhouse Gas Emissions and Sinks, https://www3.epa.gov/climatechange/ghgemissions/usinventoryreport.html

Updated: 5/3/2016
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