base period

American  

noun

1. a period of time used as a standard of comparison in measuring changes in prices, taxes, income, etc., at other periods of time.

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base period British  

noun

1. statistics a neutral period used as a standard for comparison in constructing an index to express a variable factor: 100 is usually taken as the index number for the variable in the base period

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Example Sentences

The Bureau’s consumer price index average for all items shows that over the past 50 years, the years 1982-84 provide the base period for $100.

From Washington Times • Jun. 4, 2017

Known as the Integrated Fixed Tower contract, it includes a base period quantity and options that CBP may exercise over several years.

From Reuters • Mar. 2, 2014

Currently, CBP awarded the base period quantity for a portion of the $145 million total contract amount, to be implemented over one year, Elbit said on Sunday.

From Reuters • Mar. 2, 2014

The base period for comparison purposes is now 14 years old, and the Bureau of Labor Statistics is working on a more precise and comprehensive index.

From Time Magazine Archive

Du Pont argued that during the base period it had poured millions into expansion for nylon and other new products which it did not start selling until 1939.

From Time Magazine Archive