FIRE time machine

Lesson 4 of 6, 4 minutes

What moves your FIRE date

Which inputs bring the date forward, and which of them you control.

Your FIRE date comes out of a handful of inputs, and they don't carry equal weight. Some of them you can change this month. Others you can only assume, and an assumption that turns out wrong moves the date whether you act or not.

The table below starts from one plan: age 30, spending ₹80,000 a month, investing ₹50,000 a month, with ₹10.00 L already saved. Each row changes one thing and leaves the rest alone.

One change at a time
The plan as it isage 54
Invest ₹75,000 a monthage 50
Spend ₹64,000 a month, now and in retirementage 52
Spend less and invest the differenceage 49
Earn 12% before retirementage 53
Leave no legacyage 52

Spending counts twice

Look at the rows about spending. When you need less each month, the FIRE number falls, because there is less to pay for in every month of retirement. If you also invest what you stopped spending, the corpus grows faster towards that smaller number. One decision moves both ends.

This is why cutting a recurring cost does more than a one-time saving of the same size. A subscription you cancel saves money every month until you retire, and then it lowers what retirement costs.

Returns are an assumption

A higher return brings the date forward, and it is the one row you don't control. You choose what you invest in. You don't choose what it earns. If you plan with a return you hope for and the markets deliver less, the date moves away from you in the last years, when there is the least time to adjust.

Plan with a return you would be comfortable defending to a sceptical friend. If the markets do better, you retire earlier than planned and nothing in the plan breaks.

Do this week

  1. Find your three largest recurring costs. For each one, decide whether you would choose it again today at its current price.
  2. Run your own numbers twice in the calculator, once with the return you expect and once with a return two points lower. Treat the later date as your plan.
  3. Pick the one change from the table that you could make this month, and make it before the month ends.

Change one input at a time in the calculator