This income from taxation of benefits made up about 3 percent of Social Security's income in 2016. (ssa.gov)
This income from taxation of benefits made up about 8 percent of HI Trust Fund income in 2016. (ssa.gov)
For more information about taxation of benefits, read page 14 of our Retirement Benefits booklet or IRS Publication 915, Social Security and Equivalent Railroad Retirement Benefits. (ssa.gov)