The Hispanic population living in the US is growing at the slowest rate since official record-keeping began nearly 50 years ago, according to a new report. Between 2007 and 2014, the U.S. Hispanic population grew about 2.8% annually, down from 4.4% between 2000 and 2007, and 5.8% annually in the 1990s. Mark Hugo Lopez, director of Hispanic research at Pew and a co-author of the report, said the drop is because of lower levels of legal and illegal immigration to the United States from Mexico and lower birth rates among Hispanics.