|Mandatory||Repeatable||Data Type||Authority||Level Available||A/V Only||Public Element|
|Yes*||No||Variable Character Length (2000)||None||Series
*Extent is mandatory at the Series Level only.
The measurement or amount of the archival materials themselves -- the linear measurement, page count, number of rolls, reels, cassettes, or number of data files.
Extent is related to Holdings Measurement Count and Holdings Measurement Type. All are aimed at measuring the intellectual bulk of the archival materials. Extent, being a narrative field, accommodates a wide range of units of measure, such as linear feet, pages, photographs, and so on. The element is meant to clearly communicate the amount of archival materials to the researcher. For these reasons, however, the field cannot be summed. By contrast, Holdings Measurement Type and Holdings Measurement Count, being controlled fields, can be combined to produce NARA-wide statistics about holdings.
|Purpose:||Informs users of the amount of archival materials available.|
|Relationship:||This element is dependent on Copy Status. Each copy of the archival materials must have a copy status specified to have Extent.|
Enter the measurement of the archival materials. Write a simple statement that gives the number of measurement units followed by the units of measure used. Do not use full sentences. If the extent is an estimation, the statement can be preceded by language to indicate that the measurement is estimated. If a number is longer than three digits, use commas. For example, a number should be written out as 12,877 instead of 12877.
How to Measure
Page or Item Count
If needed to clarify the amount of archival material, indicate both the intellectual count and the physical count.
Accuracy and Precision
Say "2,000 maps" instead of "2,000 items."
The extent may be estimated if necessary.