TRANSPORTATION ENERGY DATA BOOK: EDITION 22 - Center for ...

of petroleum products, and the primary stocks at the beginning of the period and then
subtracting the exports and the primary stocks at the end of the period.
Petroleum exports: Shipments of petroleum products from the 50 States and the District
of Columbia to foreign countries, Puerto Rico, the Virgin Islands, and other U.S. possessions
and territories.
Petroleum imports: All imports of crude petroleum, natural gas liquids, and petroleum
products from foreign countries and receipts from Guam, Puerto Rico, the Virgin Islands,
and the Hawaiian Trade Zone. The commodities included are crude oil, unfinished oils,
plant condensate, and refined petroleum products.
Petroleum inventories: The amounts of crude oil, unfinished oil, petroleum products, and
natural gas liquids held at refineries, at natural gas processing plants, in pipelines, at bulk
terminals operated by refining and pipeline companies, and at independent bulk terminals.
Crude oil held in storage on leases is also included; these stocks are know as primary stocks.
Secondary stocks - those held by jobbers dealers, service station operators, and consumers
-are excluded. Prior to 1975, stock held at independent bulk terminals were classified as
secondary stocks.
Petroleum products supplied: For each petroleum product, the amount supplied is
calculated by summing production, crude oil burned directly, imports, and net withdrawals
from primary stocks and subtracting exports.
Processing Gain - The amount by which the total volume of refinery output is greater than the
volume of input for given period of time. The processing gain arises when crude oil and
other hydrocarbons are processed into products that are, on average, less dense than the
input.
Processing Loss - The amount by which the total volume of refinery output is less than the volume
of input for given period of time. The processing loss arises when crude oil and other
hydrocarbons are processed into products that are, on average, more dense than the input.
Proved Reserves of Crude Oil - The estimated quantities of all liquids defined as crude oil, which
geological and engineering data demonstrate with reasonable certainty to be recoverable in
future years from known reservoirs under existing economic and operating conditions.
Quad - Quadrillion, 10 15 . In this publication, a Quad refers to Quadrillion Btu.
TRANSPORTATION ENERGY DATA BOOK: EDITION 22—2002
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