(a)  The North American Industry Classification System (NAICS) has replaced the Standard Industrial Classification (SIC) system.

  (b)  Distillate Fuel Oil includes Nos. 1, 2, and 4 fuel oils and Nos. 1, 2, and 4 diesel fuels.

  (c)  Natural Gas includes natural gas obtained from utilities, local distribution companies, and any other supplier(s), such as independent gas producers, gas brokers, marketers, and any marketing subsidiaries of utilities.

  (d)  Examples of Liquefied Petroleum Gases (LPG) are ethane, ethylene, propane, propylene,normal butane, butylene, ethane-propane mixtures, propane-butane mixtures, and isobutane produced at refineries or natural gas processing plants, including plants that fractionate raw Natural Gas Liquids (NGL).

  (e)  Other energy sources include such combustible energy sources as wood waste, hydrogen, and waste oils and tars.

    Notes:  Nominal dollars are deflated using Gross National Product chain-type indices (1996=100).  Totals may not equal sum of components because of independent rounding.   To reduce respondent burden, quantities of petroleum-based products (for example, LPG and residual and distillate fuel oil) purchased, and associated expenditures, were not collected from Petroleum Refineries, NAICS 324110.  These products are produced by petroleum refineries, rather than purchased by them.

    Source:  Energy Information Administration, Office of Energy Markets and End Use, Energy Consumption Division, Form EIA-846, '1998 Manufacturing Energy Consumption Survey.'