How to Calculate a Demographic Percentage

By Tricia Lobo; Updated April 24, 2017

Calculating percentages is an important skill to have in many disciplines, including math, science, social studies and economics. If you study statistics or demographics, you may want to demonstrate what percentage of a total population shares a certain characteristic or agrees on a particular issue.

Determine the total number of people in the population of whatever group you've chosen for study. For example, you want to determine what percentage of the population of Anytown, USA, has black hair. Start by noting that the general population, as of the start of your study, numbers 5,246.

Note the number of people who share the characteristic you're studying. Your research reveals that 789 of the town's residents have black hair.

Divide the number of residents with black hair by total population of Anytown. 789 divided by 5,246 yields 15.04%.

About the Author

Tricia Lobo has been writing since 2006. Her biomedical engineering research, "Biocompatible and pH sensitive PLGA encapsulated MnO nanocrystals for molecular and cellular MRI," was accepted in 2010 for publication in the journal "Nanoletters." Lobo earned her Bachelor of Science in biomedical engineering, with distinction, from Yale in 2010.