Author Topic: My time to FIRE calculator  (Read 2778 times)

patrickza

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My time to FIRE calculator
« on: September 07, 2016, 04:58:00 AM »
Don't ask me why, but I find putting calculators together to be a fun challenge. This one was my least challenging of all though. It tries to estimate how long you'll take to reach FIRE (or at least FI) using just three variables: Monthly net income, monthly savings and how much you already have saved.

Assumptions are a 4% draw down rate, and an investment growth rate of inflation + 5%.

Here's an example of someone earning $6000 and saving $1500 with a current stache of $200000:



Link: http://www.investorchallenge.co.za/com_calc_fire_us.php

Any thoughts?

SwordGuy

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Re: My time to FIRE calculator
« Reply #1 on: September 07, 2016, 05:37:14 AM »
Too many assumptions.  FI spending rate = current spending rate.

Savings rate will remain constant.  I might pay off the mortgage in 15 years.

Etc.

But keep plugging at it!

MDM

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Re: My time to FIRE calculator
« Reply #2 on: September 07, 2016, 09:52:48 AM »
Results appear similar to what's in Networthify's Early Retirement Calculator and the case study spreadsheet.

Differences may be due to the compounding period for "5%", e.g., annually vs. monthly vs. continuously.  Nice work!