The demography policy area encompasses a wide range of data on the people of Los Angeles County, including information on their ages, races and ethnicities, social and living arrangements, and immigration patterns. Los Angles County is one of the most populous and diverse counties in the United States. Examining characteristics about its people is an important tool for understanding how our population has grown and changed over time, and how to allocate resources in light of those changes. For example, communities with large aging populations have very different needs than those with many young children. One can also look to demography to help explain patterns and changes across our other nine policy areas on both a neighborhood and countywide level.