In my monthly scorecard, I report "Month-to-Retire" as a key metric of the progress of my retirement plan. This metric is defined by using the "retirometer" process.

Retiroment is a simple mathematical calculation that estimates number of months I need to continue work and invest my money to reach the retirement target of $1,000,000. It assumes:

Assumption #1: I'll make a monthly contribution of $2,000 into my retirement fund. That amount is after tax and after all expenses.

More often than not in the part 12 months, we can easily save more than $2,000. Especially, when my wife is working on part time jobs, we can save much more.

Assumption #2: The monthly contribution amount will increase 3% ever year to reflect earning increase and inflation.

The 3% annual contribution increase goal is less than the average US inflation rate in the last few decades (4.0%). In addition, I plan to save majority of the income increases, so a modest 2% top-line increase can translate to maybe 5% in saving increases.

Assumption #3: My retirement fund will grow 8.0% after-tax annually and compound every month.

For a long period, 8% investment return can simply be attained by investing in stock indexes. Although home value will grow much slowly, it will represent an at leat 5:1 leverage for home equity (assuming 20% down payment) and all gains below $1M are tax free. Therefore, even for the home equity part in the retirement fund pool, a growth goal of 8% per annum is still reasonable.

Admittedly, Retirometer is a very rough estimate as it does not consider asset type (real estate, car, tax-advantaged accounts vs ordinary accounts, etc.) and simplify tax effect. But as I make pretty conservative assumptions, my Retirometer is also a conservative view of my progress toward early retirement. I'm looking forward to beating the speed implied in the retiroment in the next few years.

Key output of the model:

- To start from scratch (zero retirement fund) it takes 191 months to build a net worth of $1,000,000.
- Amount to possess with X years to retirement: