For a mailing company, data entry clerks might be required to type in reference numbers for items of mail which had failed to reach their destination, so that the relevant addresses could be deleted from the database used to send the mail out. If the company was compiling a database from addresses handwritten on a questionnaire, the person typing those into the database would be a data entry clerk. In a cash office, a data entry clerk might be required to type expenses into a database using numerical codes.