i'm currently refining my wife's 403b allocations and came across a new one for me. its called a guaranteed interest account and says it yields 4%. since i'm fairly new to this(read jlcollins and know some stuff but this one throws me for a loop), is this something i should consider? i'm guessing it could take place of a bond fund, correct? how "guaranteed" is this 4%? i also can't find any info on the expense ratio and fees for it. if the 4% is guaranteed forever, would it be fairly smart to put say 80% into the vanguard 500 index(she doesn't have total stock as an option) and 20% into the GIA?