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The money for a project becomes "obligated" once the moneys have gone from the "promise" to actually being in an account.
A federal budgetary term that refers to a binding agreement that will result in an outlay; an agreement by the federal government to pay for goods or services immediately or at some future time when the goods or services are delivered; also known as a "commitment."
obligation limitation
A federal budgetary term that refers to a limit placed in appropriations bills on the amount of federal assistance that may be obligated during a specified time period; it does not affect the scheduled apportionment or allocation of funds; it just controls the rate at which these funds may be used.
Those periods of time outside the morning and afternoon peak travel periods, the nonrush hour periods when travel activity tends to be lower.
operating assistance
Financial assistance for transit operating expenses (not capital costs); such aid may originate with federal, local or state governments.
operating deficit
The sum of all operating expenses minus operating revenues.
operating expense
Moneys paid in salaries, wages, materials, supplies and equipment in order to maintain equipment and buildings, operate vehicles, rent equipment and facilities, and settle claims.
operating ratio
The percentage of revenues that goes into operating the railroad; it is calculated by dividing railway operating expenses by railway operating revenues.
operating revenue
Moneys used to fund general, day-to-day costs of running transportation systems; for transit, costs include fuel, salaries and replacement parts; for roads, operating costs involve maintaining pavement, filling potholes, paying workers' salaries, and so forth.
A periodic movement back and forth between two extreme limits; an example is the string of a guitar that has been plucked; its vibration back and forth is one oscillation; a vibration is described by its size (amplitude), its oscillation rate (frequency), and its timing (phase); in a suspension bridge, oscillation results from energy collected and stored by the bridge; if a part of the bridge has to store more energy than it is capable of storing, that part will probably fail.
A federal budgetary term that refers to a payment made to meet an obligation; the point at which an actual payment of money is made.