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 problem is a regulation that companies winning permission to raise prices must not push their profit margins�that is, their percentage of profit on each dollar of sales�above those of a base period.

From Time Magazine Archive

Under one idea now being considered in Simon's agency, consumption in excess of a certain amount�perhaps 85% of what was used during a base period last year�would be subjected to a heavy impost.

From Time Magazine Archive