"Don't get old; there's no future in it."

That was my stepfather's joke many years ago as we sat on an outdoor deck along the Florida Gulf coast, working our way through some cold beer and steamed shrimp. He died three years ago, in his mid-eighties, having lived much longer than he expected.  It could happen to any of us.

Financial planners call it "longevity risk." Like the risk of young spenders--- having too much month at the end of the money--- the older we get, the greater the chance that we'll outlive our savings. Unlike the young, many seniors have too many years at the end of the money.

Can anything be done about it?

Yes and no. Life is the greatest gift we have. Few part with it lightly. We'll have to cope by planning more and saving more--- if we have the good fortune to expect a longer than average life.

What's our first step?   Estimate the longevity risk we face. Then make decisions accordingly.

Let me give you a surprising, if personal, example. If you do a Google search for "life expectancy test" you'll come up with a long page of different 'tests.' The tests will ask you a bunch of questions. Then they estimate your life expectancy based on the information you provide. If you smoke, weigh too much, have high blood pressure, or any of the usual health worry signs, the tests will reduce your expectancy below the national averages. If you exercise, eat right, and have no family history of cancer or heart disease, the tests will increase your life expectancy above the national averages.

When I entered the information for my wife in the MSN Money life expectancy calculator, she had a life expectancy of 102 years. Yes, you read that right: 102 years. Entering a similar set of questions on the Living to 100 website, her expectancy was 102.8 years. We could average the two and call it 102.4 years but who's going to quibble? However you cut it, that's a startling number. It means planning for 40 years of senior citizenship.

When I entered the information for myself on MSN Money, my expectancy was a more modest 88 years. Living to 100 was more generous, giving me 94.8 years. Average the two and you come up with 91.4 years.

MSN Money told me I could enhance my expectancy further by losing weight or changing gender. I'll try weight loss, thank you; changing gender seems a bit extreme.

Comparable national average figures put my wife's expectancy at 83.9 years and mine at 81.3 years. This indicates a typical retirement of something over 20 years for people who retire in their early 60's, as most Americans do. While an average couple can expect a 20-plus year retirement, a healthy couple can expect nearly twice that long.

If you and yours have long expectancies, here are some of the implications:

Social Security and Medicare Stress.   The longer your expected retirement, the greater the odds you'll experience shrinking Social Security benefits and drastic changes to Medicare. There is evidence of this already: with the Medicare premium for 2005 up 17 percent from 2004, this one item absorbs much of the annual Social Security benefit increase. Today's long-lived seniors are likely to face the same funding problems today's thirty-somethings will face---except that the seniors will be facing them when they are 90 while the thirty-somethings will experience these challenges in their 60's. It won't be pretty.

Private Pension Purchasing Power.   Of the diminishing number of workers who will receive defined benefit pensions from corporations, government, and non-profit institutions, many will retire to a fool's paradise. They will fail to recognize that even a modest 3 percent inflation rate will cut the purchasing power of their pension in half in only 24 years. (I'll show what it takes to compensate for this in a future column.)

Help From children.   It is one thing to have help from your children when they are in their 50's or 60's. It's quite another for them to help when they are approaching 70 or 80 themselves. Yet many Americans will be in precisely this position. This would make Long Term Care insurance virtually imperative--- if we could confidently rely on the financial strength of the insurance industry over such a long period.

Major Upheavals.   This is a tough, unruly world. The longer we live, the greater the odds our lives, investments, and institutions will be affected by a major event--- a market crash, high inflation, a major change in our nations' position in the world.

Estate Distributions. Those fortunate enough to have an estate have to think differently if they are also long-lived. Distribution at the traditional time---death--- means your assets are likely to go to children who are over 70 years old. Earlier distributions could benefit them, and grandchildren, much more.

Margin For Error.   Compensating for all these factors means the long-lived can't cut it as close as those who will live normal life spans. The longer you live, the more you need to save. The biggest single lever for increasing your personal safety is simple. Delay retirement. Work longer.

On the web:

Figures on average life expectancies

MSN Money Life Expectancy Calculator

Living to 100 life expectancy calculator