However, due to longer life expectancies and falling birthrates, the number of people working and paying taxes has been falling relative to the number cashing benefit checks. This means higher taxes for future workers. According to Social Security's own trustees, by 2039 Social Security will be able to pay only 72 percent of promised benefits, requiring either benefit cuts of almost a third or a 50 percent tax hike on future workers. Every dollar collected by the payroll tax is immediately spent - either on current benefits or on other programs. No money is invested in real assets.
Nothing is saved.
The United States does have one, but it only exists to perform a record-keeping function. Every Social Security benefit check is written on the U.S. Treasury. Every payroll check sent to Washington is sent to the U.S. Treasury. The trust fund does not actually collect taxes, nor does it pay benefits. Technically, it holds interest-bearing bonds that represent the accounting surplus of payroll taxes collected minus benefits paid.