113570
Since pre-modern societies , by modern standards , were characterized by a very low degree of urbanization and a large majority of people working in the agricultural sector , economic historians prefer to express income in cereal units .
 cereal
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 cereal