Retirement income comes from many sources. There is the traditional pension, which many workers have. There is Social Security, which for all the doubts that swirl around it has paid benefits faithfully since its founding in the New Deal. And there are your own savings and investments.

Planners sometimes refer to this as the "three-legged stool" that supports you in retirement. But to an ever-increasing extent,the third leg, the one you provide through your own resources, is the one that makes the difference between living comfortably and struggling to make ends meet.

The work sheet on page 14, supplied by Financial Services Advisory Inc. of Silver Spring, is meant to give you a basic idea of whether you are saving enough for a comfortable retirement.

"In a nutshell," said Dave Petersen of Financial Services, "what we talking about is living for today versus saving for tomorrow." It's a balancing act, he said, as each of us seeks to choose between giving up too much today and not giving up enough to protect ourselves tomorrow.

"This work sheet is saying, let's find that balance. Some people oversave and some people aren't doing anything."

The work sheet makes several assumptions, which may not be valid in many cases or which may not fit your goals.

For one, the work sheet assumes that the income you get from your savings during retirement will rise to match inflation each year. It also assumes that all your assets would be depleted 30 years after you stop working. So if you live that long -- to age 95 if you retired at 65 -- there will be nothing left for your heirs (and nothing left for you, if you live longer).

In addition, the sheet assumes that after-tax savings and investment growth will equal inflation. In other words, the after-tax rate of return on your assets will match inflation.

And finally, it assumes that the amount you save each year while you are still working will also rise to match inflation.

All values are in today's dollars for easier understanding.

Step A. The rule of thumb for retirement planning is that you will need 70 percent to 90 percent of your current income to live comfortably. However, assess your own situation carefully. If you think you will need more, or can get by on less, adjust you number accordingly. The example in the work sheet uses 80 percent.

Step B. Current retirement savings and investment balances include the money you have in savings, the value of any stocks, bonds, real estate or other assets you have, and the balances in any employer-operated retirement accounts -- such as a 401(k) or the Thrift Plan for government workers -- and individual retirement accounts. Do not include traditional pensions that will pay monthly benefits. Those are handled below. And do not include savings that have been earmarked for other goals such as college tuition for your children.

Step C. Now calculate the annual income you can expect to receive from your savings. This payout is assumed to rise with inflation and to deplete your savings in 30 years. Multiplying the total of your savings on Line 8 by .033334 gives you this annual figure.

Step D. Next, figure out how much pensions, Social Security and other such retirement plans will pay you. Many employers that have defined benefit pension plans -- those that pay a benefit related to your length of service with the company and your pay level during your working years -- provide annual projections of the benefits youcan expect at retirement. You can use this or ask your benefits office to help you estimate your pension benefits.

Tables 1, 2 and 3 on page 13 will help you estimate your benefits if you are a federal worker and those from Social Security.

Total these benefits to get a figure for the annual income they will supply.

Steps E and F. Do you have enough? Enter your expected need, then add up your prospective income. Which is larger? If your income is larger, you should have enough for approximately 30 years of retirement. If not, you need more savings.

Step G. To determine the amount of savings you need for retirement, you need to calculate the lump sum in today's dollars that would cover the shortage on Line 19.

To do that, divide the shortage by .033334.

Now refer to Table 4 for the ratio necessary to figure the annual amount you need to save to reach the required total. In the example, seven years remain until retirement, so Table 4 shows the ratio to be .106602. Multiplying that number by the $74,999 needed in the example yields an annual savings requirement of $7,995.

Step H. Are you saving enough already? Add up whatever you are setting aside for retirement now. Include investments, IRA and 401(k) contributions (including any employer contributions).

Step I. Compare your current saving to what you need. If you are saving more than your current need, you already have a program underway that ought to meet your needs. Be sure to keep on saving.

If your current saving rate is less than the need, the difference is the amount by which you need to boost your savings. The figure on the work sheet is annual; for a monthly number, divide the annual one by 12.

Now you have a rough picture of where you stand. If the savings requirement is hopelessly large, you have three options -- retire on less, work longer or work part-time during retirement.

You could also invest more aggressively in hopes of increasing your returns, but it takes a lot of skill and no small amount of luck to do much better that the markets over the long term. Even the stock market, which has outperformed other types of investments over the long run, has averaged only about 10 percent year in and year out.

But Financial Services's Petersen says don't be too discouraged.

"A lot of people say, 'I can't retire.' I'm telling them, 'You can retire, it may just not be on what your present lifestyle is.' We all have options."