Table 4-42 ,,,,,,,,,,,,,,,,,
Estimated National Emissions of Volatile Organic Compounds (Million short tons),,,,,,,,,,,,,,,,,
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,1970,1975,1980,1985,1986,1987,1988,1989,1990,1991,1992,1993,1994,1995,1996,1997,1998
Transportation,,,,,,,,,,,,,,,,,
On-Road vehicles,12.97,10.55,8.98,9.38,8.87,8.48,8.29,7.19,6.31,6.50,6.07,6.10,6.40,5.70,5.49,R5.33,5.33
Off-Road,,,,,,,,,,,,,,,,,
  Aircraft,0.10,0.12,0.15,0.17,0.17,0.18,0.19,0.19,0.18,0.18,0.18,0.18,0.18,0.18,0.18,R0.18,0.18
  Railroads,0.02,0.03,0.03,0.04,0.04,0.04,0.04,0.04,0.05,0.05,0.05,0.05,0.05,0.05,0.05,0.05,0.05
  Marine vessels,0.01,0.01,R0.02,R0.02,R0.02,0.03,R0.03,R0.03,R0.03,R0.03,R0.03,R0.03,R0.04,R0.03,R0.03,R0.03,0.04
  Other off-roada,R0.87,R0.93,R0.98,R1.03,R1.02,R1.01,R1.01,R0.96,R0.92,R0.92,R0.91,R0.91,0.92,R0.93,R0.92,R0.92,0.92
    Total transportation,R13.97,R11.64,R10.16,R10.64,R10.12,R9.74,R9.56,R8.41,R7.49,R7.68,R7.24,R7.27,7.59,R6.89,R6.67,R6.51,6.52
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Nontransportation,,,,,,,,,,,,,,,,,
Fuel combustion,0.72,0.66,1.05,1.57,1.40,1.28,1.36,1.37,1.01,1.08,1.12,0.99,0.99,1.07,R1.04,R0.90,0.89
Industrial processesb,12.33,11.10,12.10,9.50,9.35,R9.58,9.90,9.81,9.01,9.18,9.37,9.53,9.69,9.71,R8.17,R8.39,8.02
Waste disposal and recycling,1.98,0.98,0.76,0.98,0.97,0.95,0.96,0.94,0.99,1.00,1.01,1.05,1.05,1.07,R0.42,R0.43,0.43
"Miscellaneousc, R",R1.98,R1.71,R2.22,R1.75,R1.78,R1.92,R2.54,R1.97,R2.42,R2.15,R1.91,R2.01,R2.21,R2.07,R2.43,R2.64,2.05
    Total nontransportation,R17.02,R14.45,R16.13,R13.80,R13.50,R13.73,R14.76,R14.09,R13.44,R13.43,R13.42,R13.59,R13.95,R13.93,R12.07,R12.37,11.40
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TOTAL all sourcesR,R30.98,R26.08,R26.34,R24.43,R23.62,R23.47,R24.31,R22.51,20.94,R21.10,R20.66,R20.87,R21.54,R20.82,R18.74,R18.88,17.92
"a  Other off-road comprises nonroad gasoline- and diesel-powered recreational, airport service and railway maintenance vehicles, and recreational marine vessels.",,,,,,,,,,,,,,,,,
"b  Industrial processes comprises chemical and allied product manufacturing, metals processing, petroleum and related industries, and other industrial processes; and solvent ",,,,,,,,,,,,,,,,,
"utilization, storage, and transport.",,,,,,,,,,,,,,,,,
"c   Miscellaneous comprises nonroad gasoline- and diesel-powered construction, industrial, lawn and garden, farm, light-commercial, logging vehicles, and other non-road sources; ",,,,,,,,,,,,,,,,,
"geogenic sources, catastrophic and accidental releases, health services, cooling towers, nontransportation-related fugitive dust, agriculture and forestry, ",,,,,,,,,,,,,,,,,
"structural fires, agriculture fires, slash/prescribed burning, forest wildfires,  and other combustion sources that could not be accurately allocated to specific source categories.",,,,,,,,,,,,,,,,,
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KEY: R = revised.,,,,,,,,,,,,,,,,,
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NOTES: The methodologies used to estimate emissions constantly evolve and undergo major changes.  These improved methods are,,,,,,,,,,,,,,,,,
"often used to revise estimates for previous years.  Therefore, some estimates in this table may not match estimates produced in previous",,,,,,,,,,,,,,,,,
"reports, and some trends may not be consistent across years in which major methodology changes have occurred.",,,,,,,,,,,,,,,,
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Numbers may not add to totals due to rounding.,,,,,,,,,,,,,,,,
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"SOURCES:  U.S. Environmental Protection Agency, National Air Pollutant Emission Trends: 1900-1998 (EPA-454/R-00-002) (Research Triangle Park, NC: March 2000), table A-3; also available at",,,,,,,,,,,,,,,,
"Internet website www.epa.gov/ttn/chief/trends98/emtrnd.html, as of Aug. 8, 2000. ",,,,,,,,,,,,,,,,
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