vichinterlang/iStock(WASHINGTON) — The number of unauthorized immigrants living in the U.S. hit a new low in 2017, according to estimates released Wednesday by the Pew Research Center.About 10.5 million lived in the U.S. in 2017 without citizenship or legal authorization. That’s down from a peak of 12.2 million estimated in 2007, according to Pew. The new report found the decline was largely driven by Mexicans leaving the U.S.The data used in the report pre-dates the current surge of Central American migrants which have overwhelmed federal authorities at the southern border.But the 2017 data shows that significant growth in the unauthorized population came from Central America. Mexicans no longer made up the majority of the unauthorized population for the first time since 1965.Since 2007 the number of unauthorized Mexican immigrants declined by about 2 million. Other increases in migration came from Asia and South America.Researchers found unauthorized immigrants are staying longer in the U.S. The average person had lived in the country for 15 years in 2017, the longest track record of residency since 1995.The data in the report came from census information, survey data and immigration records.Copyright © 2019, ABC Radio. All rights reserved.