The greatest threat to the U.S. budget stability in the coming decade is the growth of federal spending on healthcare, according to the Congressional Budget Office (CBO), which found that spending for Medicare and Medicaid, under current law, is expected to keep growing faster than the economy, reaching 6.6 percent of the gross domestic product by 2020 and potentially reaching 10 percent by 2035.
The CBO also estimated that Social Security, Medicare and Medicaid will account for about 70 percent of mandatory, or direct spending in 2010, excluding offsetting receipts.
According to the CBO, 76 million people, a 10 million increase from 2009's 66 million participants, will be enrolled in Medicaid in 2020, equaling $428 billion, or 2 percent, of gross domestic product spending. Medicare's spending is estimated to exceed $1 trillion in 2020 with the anticipation that future spending for Medicare will grow by an average of 7 percent annually over the coming decade.
This figure would result in increasing Medicare spending as a percentage of gross domestic product from 3.5 percent in 2009 to 4.6 percent by 2020.
In 2009, Medicare had about 46 million beneficiaries; by 2020 that number is expected to climb to 61 million, according to the CBO.