Custom geocoding is a flexible option that enables you to apply your own type of lookup data to your address data. For example, your input address data might include only telephone area codes for different customers. Other examples are internal sales territories and Metropolitan Statistical Areas (MSA).

Use the option METHOD=geocoding-method to specify CUSTOM when you want to geocode an unconventional, non-address type of lookup variable. You must use the option ADDRESSVAR=variable to identify the address variable in your address data. You must also use the option LOOKUPVAR=variable to identify the non-address variable in the lookup data set.

Any data can be used as lookup data with the CUSTOM method of geocoding. The only requirement is that you have at least three variables. The variables must be the projected or unprojected coordinate values (X and Y or LAT and LONG), and include a key variable to look up.

You can specify that non-geocoding variables such as COUNTY, TIME ZONE, and AREA CODE from the lookup data set be added to the output data set. Do this by using the ATTRIBUTEVAR= option in the PROC GEOCODE statement.