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2. Date : If day or month are entered, segment then 'Segment' is unselectable.
3. Period
4. Before (or After) : There's a default value for calculating 'Earliest Date' but it can be overridden.
5. Century 
6. Century by year (like Century, but a different display format)
2. In the current system date display text is sometimes more detailed than the date ranges.
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