For the first time in 27 years, the U.S. government is changing how it categorizes people by race and ethnicity. The goal is to more accurately count residents, including those who identify as Hispanic and of Middle Eastern and North African heritage. The revisions announced Thursday are the latest efforts to categorize and define the people of the United States. This evolving process often reflects changes in social attitudes and immigration. Under the revisions, questions about race and ethnicity that previously were asked separately will be combined into a single question. A Middle Eastern and North African category also will be created.