So, a
recent thread over on Bogleheads got me thinking about
The Shockingly Simple Math Behind ER.
However, it still isn't all that simple on the calculation side, and people still get hung up on it when thinking about pre-tax, post-tax, employer added income, etc.
But couldn't you re-formulate the table as a percentage of expenses? It seems that would be way easier to calculate. Like:
95% savings rate = 19x expenses -> <2yrs
50% savings rate = 1x expenses -> 17yrs
35% savings rate = 0.54x expenses -> 25yrs
25% savings rate = 0.33x expenses -> 32yrs
10% savings rate = 0.11x expenses -> 51yrs
Then, the calculation is really easy: I spent $55k and saved $32k (as in, this amount somehow made it into my various retirement accounts). So, 32/55 = 0.58, which is about 25yrs.
Does anyone have the spreadsheet for the math to verify if you can reformulate it this way? Did I miss something? (Probably! Or someone else would have already done it this way!)