::U.S. post code follows the pattern [five digits - four digits]. In this way, U.S. patents can be extracted by searching for post code with regular expression.
::For example,
city | postcode_city
OALKLAND, CA 94612-3550 | 94612-3550
OXFORD CT 06483-1011 | 06483-1011
::The extracted post code records are stored in table ptoassigneend_missus_final.