No it hasn't. It is a pay as you go system. Any "surplus" is deposited into the General Fund and the Treasury issues non-market T-bills in the amount of the surplus for deposit into the SSTF. Actually, those are IOUs. Here is the 1983 law: P.L. 98-21, (H.R. 1900)
Without using the "surplus" the USG would have to borrow real money to fund operations. They would then have to raise taxes or curtail spending. It is far easier to maintain the charade of a separate SS that is really just another form of income tax. Approximately 80% of Americans pay more in payroll taxes than they do in income taxes.
I beg to differ.
In 1983 the SS tax was raised not for current expenditures, which was well in hand then.
It was raised specifically to avert the crisis that would come in the 2015 time range when the Boomers were in massive retirement and drawing benefits.
SS has not been on pay as you go at least since then.
In fact excess collected SS funds have been cycled into current expenditure funds since 1967.
A policy put in place by Lyndon Johnson.
Another Democrat.