According to CBO's estimates, 154 million Americans under the age of 65 currently have an employment-based health insurance plan as their primary source of coverage, and several million other people have primary health insurance coverage purchased directly from an insurer. National health expenditures in 2011 were about $2.7 trillion, of which private insurance financed about one-third. Much of the agency’s recent work in this area has focused on the effects of the Affordable Care Act on private health insurance.