
The golden rule in the financial independence/retire early (FIRE) space is to amass investable assets worth 25 times your annual expenses, that is, you live off 4% of your investments, adjusted for inflation. So, during the first year of retirement, you withdraw 4%, during the second year, 3% plus the amount needed to cover inflation, and so on.
The original financial planner that introduced this idea was William P. Bengen. If you want to dig into his article, Determining Withdrawal Rates Using Historical Data. His work in 1964 was followed up in 1998, by three professors of finance in the Department of Business Administration, Trinity University, San Antonio, Texas, affectionately nicknamed the Trinity Study.
The Trinity Study analyzed withdrawal periods up to 30 years. While it did not account for taxes and transaction fees, the study did account for inflation. The Study concluded that stock-dominated portfolios (75% stock/25% bonds) would last 30 years 98% of the time based on all historical data.
Plus, the math is easy with the 4% rule. Examples are often represented by showing someone that can live on $40,000/year (though in most places, I would consider that EXTREMELY frugal). They just need to make it to the 2 comma club for a nest egg of $1,000,000 to FIRE.
$40,000 / 4% = $1,000,000
Or as it is more commonly stated
$40,000 x 25 = $1,000,000
In the second year of FIRE, adjust for 3% inflation and you would withdraw:
$40,000 x 1.03 = $41,200
Should I trust the 4% rule?
When you are starting from a negative net worth (more debt than assets), or you’re socking away your first $100,000, your FIRE number is just a concept to move you to action. It doesn’t really need to be that accurate. But the closer you get, the more comfortable you need to be with that number.
The key finding from the Trinity study that keeps me from blindly following the 4% rule is the very first conclusion they draw,
“Early retirees who anticipate long payout periods should plan on lower withdrawal rates.”
I’m looking at 45-50 years here and FIRE is no longer an abstract concept. I don’t feel like abstract generalizations are good enough anymore, so my FIRE number has become more complicated. I use a more conservative 3.5% withdrawal rate for my planning purposes.
Our income in retirement will come from a pension for Mr. FIF and assets invested primarily in low cost index funds. We will also keep our mortgage with a rate of 2.875%. It is unusual for early retirees to keep the mortgage, but it is our only debt and that rate is amazing!
In order for us to feel confident in our financial independence, I have broken out our FIRE plan into these four components:
FIRE Component | Annual Expense | The Explanation | FIRE # |
Kid’s College (529s) | Present Value of $25K/yr for 8 yrs | $175,000 | |
Mortgage | $22,000 | Estimate 100% success based on historical returns | $400,000 |
Spending over Pension (not including mortgage) | $28,000 | Using a safe withdrawal rate of 3.5% or $28,000/3.5% | $800,000 |
Cash Cushion | 2x Annual expense of mortgage and spending over pension or ($22,000+$28,000)*2 | $100,000 | |
Total | $1,475,000 | ||
Total w/o 529’s | $1,300,000 |
Expenses, the real key to FIRE
I’ve tracked our net worth since 2010 because I’m a money nerd. I used Microsoft Money originally, but Microsoft quit supporting it, so then I used Quicken for many years, but then I got very annoyed with their insistence on forcing me to update (read: PAY) for a new version every 2 years, or they would no longer support importing my account balances. Enter Mint, Personal Capital, and so many spreadsheets. I’ve settled on a single spreadsheet, the FI Family Google Sheet, plus Personal Capital.
Mint is ok for tracking expenses, but Personal Capital does that too and so much more. I love the dashboard. It offers a snapshot of my net worth (to the extent I’ve loaded all my accounts into it). It also shows a budget widget that compares how much I’ve spent to last month. I only have two complaints for Personal Capital. One is that two-factor authentication (the additional annoying step of needing to get a code texted to you) for my bank and investment accounts often break the import. Sometimes it fixes itself and sometimes I have to spend too much time figuring out why it doesn’t work. The second annoyance is that once you have $100,000, they offer a “free” call with one of their advisors. Remember, as the saying goes, if the product is free; you’re the product. Have no doubt, with Personal Capital; you are the product. I still look at it almost every day though for a quick and easy estimate.
I ended up building a Google Sheet that tracks my annual net worth as in the above picture. It also tracks monthly net worth for the current year, monthly income and spending, and all of my quirky FI calculations. I still need to clean it up and put some dummy numbers and instructions in it, and then I’ll offer it to the masses or the three of you reading one of my first posts.
Where are we on our FIRE journey?
*Updated as of April 24, 2021
For the sake of consistency, I’ll only report on my invested assets in order to track the family’s journey towards financial independence. I also won’t include the 529 balances since I won’t be able to withdraw from those investments for living expenses in early retirement. What we’re left with are Financial Independence (FI) Assets.
April 1, 2021, FI Assets $989,937
I assume a 6% real return, with $6000 monthly investment contributions.
Date | Contributions | Real Returns | Estimated FI Assets |
4/1/2021 | $989,937 | ||
4/1/2022 | $72,000 | $59,396 | $1,121,333 |
4/1/2023 | $72,000 | $67,280 | $1,260,613 |
Monthly | |||
5/1/2023 | $6,000 | $6,303 | $1,272,916 |
6/1/2023 | $6,000 | $6,365 | $1,285,281 |
7/1/2023 | $6,000 | $6,426 | $1,297,707 |
8/1/2023 | $6,000 | $6,489 | $1,310,196 |
While there are general rounding errors in the above table due to switching from annual to monthly calculations, it is good enough to illustrate how we come to the FIRE date of 2 years and 4 months left to early retirement.
That’s really exciting that you’ve reached the millionaire level! Tracking investments is a pet project of my partner, and he’s gonna love this chart you’ve shared. Thanks!