ericm979
Super Member
- Joined
- Nov 25, 2016
- Messages
- 5,817
- Location
- Santa Cruz Mountains CA, Southern OR
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- Branson 3725H Deere 5105
The 25x guideline will never dip into the principal if you can maintain a 4% return AND (and this is the rub) your expenses don't increase with inflation. However, today it's pretty hard to find 4% without some risk to the capital (even bonds have some risk of capital loss). Assuming you have a mix of investments, it will probably exceed 4% over time but you need some margin and some of that gain is just keeping up with inflation.
4% is commonly used because the long term average return on the market is about 7%, and when you subtract an expected inflation of 3% you get 4%. Some people assume 2% inflation and use 5%, but while 2% is the fed's current inflation target it's lower than the 3.2% long term average and is probably optimistic.
But you're correct that if you move some money into lower return investments as many people do, you'll probably be getting less than 4% after inflation.
The 4% thing is just a handy rule of thumb. I'm not confident using a rule of thumb to plan my retirement, I use more accurate models.