data item proportion of population in an elementary occupation A data item that is the output of some data transformation that takes as input the number of individuals in a population who are occupation holders and has as output the proportion of those individuals who are classified by the European Skills, Competences, Qualifications and Occupations as door-to-door sales worker, news or street vendors; building cleaning workers; pressers, textile, garment, or related materials; septic tank servicers or sewer pipe cleaners; farmworkers or laborers, crop, nursery, or greenhouse; farmworkers, farm, ranch, or aquacultural animal; agricultural workers, all other; landscaping or groundskeeping workers; grounds maintenance workers, all other; forest or conservation workers; logging workers, all other; fishing or hunting workers; helpers--extraction workers; extraction workers, all other; helpers, construction trades; rail-track laying or maintenance equipment operators; construction laborers; helpers--production workers; production workers, all other; laborers or material movers; refuse or recyclable material collectors; couriers or messengers; material moving workers, all other; aircraft cargo handling supervisors; first-line supervisors of helpers, laborer, or material mover, hand; first-line supervisors of transportation worker, all other; tank car, truck, or ship loaders; cooks, fast food; cooks, short order; food preparation workers; dining room or cafeteria attendants or bartender helpers; dishwashers; food preparation or serving related workers, all other; personal care or service workers, all other; baggage porters or bellhops; maintenance or repair workers, general; installation, maintenance, or repair workers, all other; meter readers, utilities; coin, vending, or amusement machine servicers or repairers; motion picture projectionists; ushers, lobby attendants, or ticket takers; amusement or recreation attendants; locker room, coatroom, or dressing room attendants; and parking attendants. Currently, the Occupation Ontology (OccO ) only represents occupations as they are defined by O*NET. We define this class extentionally according to the O*NET-defined occupations that map to occupations in ESCO that are classified as elementary occupations. Matthew Diller William R. Hogan