Usual Occupation, Industry, and Class of Worker:
Enter that occupation which the person regards as his usual occupation and at which he is physically able to work. If the person is unable to determine this, enter that occupation at which he has worked longest during the past 10 years and at which he is physically able to work. Enter also usual industry and usual class of worker.

619. Columns 45 to 47. Usual Occupation, Usual Industry, and Usual Class of Worker.-Inquiries 45 to 47 are to be answered for all persons 14 years old and over.

623. Columns 46 and 47. Usual Industry and Usual Class of Worker.-Enter cols. 46 and 47 the appropriate entries to indicate the usual industry and usual class of worker, in accordance with the instructions for entering these items in cols. 29 and 30. (See pars. 548 to 575.) The usual industry and usual class of worker will be those, relating to his usual occupation, which the person regards as the usual ones. These entries may or may not be the same as the corresponding entries in cols. 29 and 30.