National Hispanic Heritage Month, which begins each year on Sept. 15, celebrates U.S. Latinos, their culture and their history. Started in 1968 by Congress as Hispanic Heritage Week, it was expanded to a month in 1988. The celebration begins in the middle rather than the start of September because it coincides with national independence days in several Latin American countries: Guatemala, Honduras, El Salvador, Nicaragua and Costa Rica celebrate theirs on Sept. 15, followed by Mexico on Sept. 16, Chile on Sept. 18 and Belize on Sept 21.

Here are some key facts about the nation’s Latino population by age, geography and origin groups.