The increase in undocumented immigration between 1999 and 2007 contributed to an increase in the number of uninsured people in the United States. During this period, the number of undocumented immigrants increased from an estimated 8.5 million to 11.8 million, leading to an estimated additional 1.8 million uninsured. Undocumented immigrants accounted for one in seven of the uninsured in 2007, up from one in eight in 1999. Since undocumented immigrants will not be eligible for public insurance or private coverage obtained through exchanges under the Affordable Care Act, they will eventually constitute a larger percentage of the uninsured population.