This layer contains lines showing how parcels were historically divided in the Assessor's database, where two or more lots were merged into a single parcel. When the layer was originally created, it was used to illustrate lots that were owned and used in common and were combined to form a "main lot" for valuation purposes. More recently, any parcels that are merged trigger the creation of a sited parcel line to retain a historical record of the original parcel boundaries. Historical parcel IDs can be found in the "Supplemental Data" area in the assessing database.