You spend your whole career saving for retirement so that you'll have the money you need after you stop working. But when it comes time to actually get that money, what's the best way to do it?

In the following video from our Motley Fool Live Financial Planning Power Hour series, longtime Motley Fool contributor and Director of Investment Planning Dan Caplinger discusses the rules governing taking money out of tax-favored retirement accounts. As Dan explains, you're required to take money out of some of your accounts, or else you'll owe considerable penalties to the IRS. By making smart decisions across all your retirement savings, you can get the money you need in a tax-smart way.

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If you're like most Americans, you're a few years (or more) behind on your retirement savings. But a handful of little-known "Social Security secrets" could help ensure a boost in your retirement income. For example: one easy trick could pay you as much as $16,728 more... each year! Once you learn how to maximize your Social Security benefits, we think you could retire confidently with the peace of mind we're all after. Simply click here to discover how to learn more about these strategies.

Dan Caplinger: Danny asks, "Could you explain minimum distribution rules for retirement accounts? Is it a certain minimum amount each year?"

Danny, it's a long topic. If you do a search on my name and RMD for required minimum distributions, you're going to get some articles. I didn't have a chance to find one right now, but you're going to find some articles that give you a lot of details.

But let me just sum it up really quick. We have got about seven minutes left. I'm not going to take all of that time. In general, the point of the RMD rules is they're trying to get you to take out a certain percentage of your retirement assets each year. That percentage corresponds to your expected life expectancy for that year so that if say your life expectancy is 20 years, usually the IRS is going to say, "Hey, we want you to take 1/20th of that money out, or 5%." It doesn't always work that way, but that's really the general idea.

Then, as you get older, they're going to say, "Hey, you should take out a larger percentage of it because you're getting closer to using it up." Ideally, the IRS wants you can use up that money right in time for the end of your life so that you have very little left at the time that you pass away.

Now, is it a specific amount? No, it's not. It is a specific percentage, but that percentage changes from year to year as you get older. So it's not just a simple, "Did I take my $5,000 this year?" No, you have got to calculate it separately every year. That calculation is based not only on your new age, but also on the change in the value of your retirement accounts.

So if your retirement accounts values went way up, then yeah, you're going to owe a bigger RMD the following year because the percentage is going to be of a larger amount, so that total amount ends up going up. I hope that's a good short description of what we're talking about here. But as far as the calculations are concerned, most financial institutions will help you out with the calculations. So if it's really just a dollar amount that you're looking for, talk to the folks that you have your IRA with, they should be able to help you.