Ch. 2 Notes Agricultural density- the ratio of the number of farmers to the total amount of arable land Arithmetic density- the total number of people divided by the total of land area Census- a complete enumeration of a population Nonparticipation- homeless people, ethnic minorities, and citizens of other countries who don?t have proper immigration documents may be less likely to complete census forms Sampling- statistical sampling techniques can be utilized to get a more accurate count, as well as to identify detailed characteristics of people, housing, and businesses. Crude birth rate- the total number of live births in a year for every 1,000 people alive in the society Crude death rate- the total number of deaths in a year for every 1,000 people alive in the society