Our plan is extremely simple... On the spending side, we have three different budgets that we can adjust as circumstances warrant. Best case... Nominal... and Austerity.
On the Asset/Nest Egg side, We boil our assets down into three categories.
1. Fixed assets... house, auto, and other valuable non cash items... real property, jewelry, . We do not count household goods... (experience tells us that this is not realistic)
2. Non Income producing assets... bank accounts, cash, cash value life insurance policies.
3. Income producing assets... stocks, bonds, annuity.
All of these items are kept on a spread sheet and periodically updated. It's easy to come up with a total value... and then to average the income from the total...
To calculate where we stand in our retirement plan, we add
a. Social security amount.
b. Amount of interest earned on income producing assets.
c. ... and add the Total Assets divided by the number of years between now and age 85.