I’m looking for date fields.

Or more specifically, I have been given a pile o’ MARC records, and I will be extracting for analysis the values of dates from MARC 260$c. From the resulting set of values — which will include all sorts of string values ([1900], c1900, 190?, 19—, 1900, etc.) — I plan to normalize things to integers like 1900. I then want to save/store these normalized values back to my local set of MARC records. I will then re-read the data to create things like timelines, to answer questions like “How old is old?”, or to “simply” look for trends in the data.

What field would y’all suggest I use to store my normalized date content?

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Eric Morgan