It is your number. It may be the same number as someone else, but that similarity is merely interesting. Your retirement number is the amount that you need to accumulate and call your capital. Capital is used over and over again and continues to grow for you (erratically but continually) while it provides you an income you add to your other “guaranteed” sources. Will you receive a social security payment monthly, a group retirement payment that will end when you or your wife or significant other die, and any additional payments that will come to an end because you have spent all the money, or, chosen a payment that will be switched to the issuing security? Preferably, it is the number providing you the income you need each month. Everyone spends differently so the capital needed is dependent on cash flows out. Call us for how to use and understand.