For the longest time, I thought I was the kind of person who would never retire.

I love being a journalist, and not retiring runs in my family. My grandfather literally worked until the day he died, exactly the way he had wanted.

But having a job — a 40-hour a week commitment that prevents me from traveling more than two weeks a year — has helped me realize why people want to retire. Retirement is a profession that gives you a whole lot more time.

At some point in the past couple of years, I decided I wanted to have the option to retire by 27, ideally with $1 million in the bank. With my 27th birthday approaching next month, it's becoming increasingly clear that it's not going to happen.

It makes perfect sense, really.

I'm not a celebrity, athlete, dot-com genius or lottery winner. And I didn't start working full-time until I was 23.

The equation four years of work at a normal-paying job equals comfortable retirement is one that just doesn't work.

But there are more realistic equations. Kiplinger's Personal Finance details some in its February edition.

To make $1 million by the age of 65, a 25-year-old would need to save $286 a month, the magazine says. Starting from scratch at age 35 would require a monthly savings of $671 a month. Wait until 45, and that figure rises to a whopping $1,698 a month.

Wait until 55 to start saving, and you might just want to give up on the notion of retiring a millionaire. At that age, you'd need to save $5,466 a month to retire a millionaire, according to Kiplinger's calculations.

Clearly, the younger you are when you start saving, the easier it is to plan to retire a millionaire. Not only do you have more time to save, but you also have more time to profit from a beautiful concept called compounding interest: The earning of interest on the interest you've already earned.

An additional 10 years in compounding interest could add more than $250,000 to $100 in monthly retirement savings, according to Kiplinger's.

Kiplinger's says a person who saves $100 a month starting at age 22 and earns 8 percent on the money until he or she turns 65 will have $450,470. Starting at age 32 would result in just $194,654.

The $450,470 definitely sounds better, especially when you realize that the extra $250,000 you're getting comes from just an additional $12,000 in savings.

That's a nice chunk of compounded interest.

Retiring by 27 might not be realistic unless you’re Beyoncé or a twin with the last name of Olsen. But starting to plan for retirement by that age clearly is the way to go if you're just a normal person who wants to retire a millionaire.