What methods would you use for determining a demand for cotton balls?

Demand for cotton balls is usually determined based on the population size and the number of medical centers. The demand will vary depending on how much cotton is required per patient (which depends on their condition).

Explanation:

The population size would be calculated by multiplying current population rates by estimated future rates. These calculations can be difficult, since they require available data about birthrates, death rates, and migration patterns to determine current population growth.  

The number of medical centers represents primary care points for patients that need more than just over-the-counter treatment. Population statistics are also used in calculating this figure because it incorporates total number of people sought medical attention each year, which relates to demand for medacins.