Notes
1. Matching payments from the general fund, plus certain interest-adjustment items.
2. Other income includes recoveries of amounts reimbursed from the account that are not obligations of the account and other small amounts of miscellaneous income.  In 2008, includes an adjustment of $812 million for interest inadvertently unearned as a result of HI hospice costs that were misallocated to, and paid from, the Part B account from May 2005 to September 2007.
3. Values after 2005 include additional premiums for Medicare Advantage (MA) plans that are deducted from beneficiaries' Social Security checks. These additional premiums are beneficiary obligations and occur when a beneficiary chooses an MA plan whose monthly plan payment exceeds the benchmark amount. Beneficiaries subject to such premiums may choose to either reimburse the plans directly or have the premiums deducted from their Social Security checks. The premiums deducted from the Social Security checks are transferred to the HI and SMI trust funds and then transferred from the trust funds to the plans.
4. Includes costs of Peer Review Organizations from 1983 through 2001 and costs of Quality Improvement Organizations beginning in 2002. 
5. The financial status of Part B depends on both the assets and the liabilities of the account.
6. Section 708 of Title VII of the Social Security Act modifies the provisions for the delivery of Social Security benefit checks when the regularly designated delivery day falls on a Saturday, Sunday, or legal public holiday. Delivery of benefit checks normally due January 3, 1982 occurred on December 31, 1981. Consequently, the Part B premiums withheld from the checks ($264 million) and the associated general revenue contributions ($883 million) were added to the SMI trust fund on December 31, 1981. These amounts are excluded from the premium income and general revenue income for calendar year 1982.
7. Delivery of benefit checks normally due January 3, 1988 occurred on December 31, 1987. Consequently, the Part B premiums withheld from the checks ($692 million) and the associated general revenue contributions ($2,178 million) were added to the SMI trust fund on December 31, 1987. These amounts are excluded from the premium income and general revenue income for calendar year 1988 (refer to note 6).
8.1989 includes the impact of the Medicare Catastrophic Coverage Act of 1988 (Public Law 100-360).
9. Delivery of benefit checks normally due January 3, 1993 occurred on December 31, 1992. Consequently, the Part B premiums withheld from the checks ($1,089 million) and the associated general revenue contributions ($3,175 million) were added to the SMI trust fund on December 31, 1992. These amounts are excluded from the premium income and general revenue income for calendar year 1993 (refer to note 6).
10. Includes the impact of the transfer to the Hospital Insurance (HI) trust fund of the SMI catastrophic coverage reserve fund on March 31, 1993, as specified in Public Law 102-394. Actual benefit payments for 1993 were $53,979 million and the amount transferred was $1,805 million.
11. Delivery of benefit checks normally due January 3, 1999 occurred on December 31, 1998. Consequently, the Part B premiums withheld from the checks ($1,512 million) and the associated general revenue contributions ($4,711 million) were added to the SMI trust fund on December 31, 1998. These amounts are excluded from the premium income and general revenue income for calendar year 1999 (refer to note 6).
12. In 1998-2003 benefit payments less monies transferred from the HI trust fund for home health agency costs, as provided for by the Balanced Budget Act of 1997.
13. In 2005-2007 certain HI hospice costs were misallocated to, and paid from, the Part B account.  See also note 14.
14. 2008 benefit payments were $188,797 million. Amount shown in 2008 includes -$8,484 million, which represents a transfer from the general fund of the Treasury to the Part B account for HI hospice costs that were misallocated to, and paid from, the Part B account from May 2005 to September 2007. (The HI trust fund, in turn, transferred $8,484 million to the general fund.)
15. Delivery of benefit checks normally due January 3, 2010 occurred on December 31, 2009 and those normally due January 3, 2016 occurred December 31, 2015.  Consequently, the Part B premiums ($3,861 million) withheld from these benefits and the associated general revenue contributions ($10,930 million) were added to the Part B account on December 31, 2009.  Part B premiums ($2,097 million) withheld from these benefits and the associated general revenue contributions ($5,446 million) were added to the Part B account on December 31, 2015.These amounts are excluded from the premium income and general revenue income for calendar year 2010 and 2016, respectively (refer to note 6).
Note: Totals do not necessarily equal the sums of rounded components.
