Disclosed is a system method for aligning a plurality of electronic map data, which includes the steps of obtaining an electronic map file, defining an area of interest on the electronic map file, selecting a predetermined datum and providing the electronic map file in the predetermined datum. Also disclosed is a land yield method including the steps of obtaining an electronic map, storing the electronic map in a computer readable medium, defining an area of interest on the electronic map, referring to a database to determine whether the database contains at least one restriction value, referring to a remote database to determine whether the remote database contains an additional restriction value, the additional restriction value being distinct from the at least one restriction value, combining restriction values, and determining a total value of the parcel of land based on the combined restriction values.