Also known as "Parcel" level, a rooftop precision level represents actual data where the latitude and longitude coordinates plot in the center of the parcel boundary associated with the physical address. Typically these points are at the rooftop of the building.
Also known as "Site" level, interpolated rooftop coordinates are estimated through a proprietary interpolation algorithm using known street segment ranges with the address numbers.
For example, if a street segment is 100 to 200 Main Street and there are five known addresses on that side of the street, the coordinates are evenly spaced out in fifths along that street segment.
Address parity is used to determine which side of the street an address falls. If the address falls on the left side of the street, then the coordinates are shifted to the left. If it is on the right side of the street, the coordinates are shifted to the right.
ZIP+4 Centroid coordinates are plotted at the geographic center of the 9-digit ZIP+4 area, which is about the size of a city block.
ZIP+2 Centroid coordinates are plotted to the geographic center of the 7-digit ZIP+2 area, which is usually the size of a neighborhood or business district.
ZIP Centroids are plotted to the geographic center of the 5-digit ZIP area.