Use this feature to ensure that on the one hand your sales team is always working with current data and on the other hand keep historic data. Take care to manage the following data meticulously:
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- Site,
- Placement,
- Ad Type
- AdServer Id's,
- Keys and Values,
- Content,
- City, Region, Country (old GeoTargeting)
- Ad Price
- Rate Card
Afterwards activate the feature in the administrative settings by setting "Filter for active records". 
Result: Only records with an active checkbox set to TRUE of the listed objects are shown to users in the following wizards or lookup features:
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