Chris616
Silver Member
There is a standard way to compare two series of payments, like receiving a smaller monthly SS amount from age 62 onwards vs a larger amount age 67+, in order to make an "apples to apples" comparison. The series of payments is converted to one single equivalent number that is called the "present value" or "future value" depending on which direction the conversion is going.
I used a spreadsheet for the attached screenshot (and I've pasted in the formulas in that red box for anyone who wants to recreate it), but you can find PV and FV calculators online, like this one (I pasted in the same calculation to show that it gives the same answer):
Present Value Calculator
In the spreadsheet, line 10 gives the "present value" in the year 2024 of the $2500 payments made from age 67 onwards.
Line 14 is the sum of the preceding two lines and is the number to compare to line 10.
Line 12 gives the "present value" in the year 2024 of the $1750 payments made from age 67 onwards.
Line 13 gives the "future value" in the year 2024 of the $1750 payments made from age 62-67 (2019-2024).
The "Interest rate 67+" isn't significant, since it has the same impact on lines 10 and 12. What does make a difference is the interest rate applied to the monthly payments received from age 62-67. In this example I've adjusted that interest rate (cell B6) until I got the same total for the two options (this is what David was trying to do).
If you bring the "Interest rate 62-67" down to 2% to match the other interest rate, you can then adjust the "Expiry age" downwards to see at what age the two options are equivalent. That's age 81 for this example.
Chris

I used a spreadsheet for the attached screenshot (and I've pasted in the formulas in that red box for anyone who wants to recreate it), but you can find PV and FV calculators online, like this one (I pasted in the same calculation to show that it gives the same answer):
Present Value Calculator
In the spreadsheet, line 10 gives the "present value" in the year 2024 of the $2500 payments made from age 67 onwards.
Line 14 is the sum of the preceding two lines and is the number to compare to line 10.
Line 12 gives the "present value" in the year 2024 of the $1750 payments made from age 67 onwards.
Line 13 gives the "future value" in the year 2024 of the $1750 payments made from age 62-67 (2019-2024).
The "Interest rate 67+" isn't significant, since it has the same impact on lines 10 and 12. What does make a difference is the interest rate applied to the monthly payments received from age 62-67. In this example I've adjusted that interest rate (cell B6) until I got the same total for the two options (this is what David was trying to do).
If you bring the "Interest rate 62-67" down to 2% to match the other interest rate, you can then adjust the "Expiry age" downwards to see at what age the two options are equivalent. That's age 81 for this example.
Chris
