Regarding taking Social Security(SS) at age 70 instead of full retirement age (FRA), I don’t understand the mathematical justification for doing this.
Let’s make several assumptions: One can assume that readers of this blog do not need SS to live on. If this is correct , then the goal of receiving SS should be the total benefit over a lifetime. This lifetime benefit is a simple math equation: x times y = total lifetime benefit where x = annual SS benefit and y= number of years the benefit is collected.
If I delay taking SS until age 70 instead of 66 ( my full retirement age, FRA), the annual benefit of an additional 8% compounded annually for 4 years = a benefit of 1.35x per year. Thus, the lifetime benefit starting at age 70 is 1.35x( y-4).
So let’s start trying to figure out when delaying taking SS becomes better than taking SS at age 66. This is calculated by the equation xy-= 1.35x (y-4). In this case, y=‘15.7 years. So if I start taking my SS at age 66, I will be 81.7 yo at a time that my lifetime SS benefit will be exactly equal; whether starting at 66yo or 70yo. Every year thereafter, I will have done better by waiting until age 70. However, if I take SS money at 66yo and invest the money, I can easily make 3% a year in various investments, and that will delay the break even point to 22 years, at a time i will be 88yo. If I can earn 5% which is also not very difficult, the break even point is 35years, at a time I will be 101 years old.
Therefore investing the SS proceeds at even a small rate of return (2-5%) seems to make it much more valuable to start taking SS at my full retirement age, as long as one is willing to take the risk that in my late 80's or even my 90's, I may recognize that I could have collected a larger lifetime benefit by starting at age 70 rather than my FRA. But at that point, being a high income saver up to this point in my life, who really cares?.
Comment