If you're not investing for retirement, you've got some explaining to do. And so do many others. According to the Employee Benefit Research Institute's (EBRI) 2013 Retirement Confidence Survey, only 66% of Americans have saved money for retirement, and nearly half (46%) have saved less than $10,000. A recent American Consumer Credit Counseling poll found that about 30% of Americans are not contributing to a retirement account at all. There are lots of reasons people might offer for not investing for retirement -- but few of them hold water. Let's examine some.

Too young
It's a big shame when young people don't invest, since they have the most to gain from it, even if they're not cash-rich. They have time. If you're 15, you have a whopping 50 years until a typical retirement age. And even at 25, you have 40 years. Put off investing for retirement until you're 45, and you'll have to work much harder at it, with only 20 years in which to grow a nest egg. A single $1,000 investment growing at 8% annually will approach $47,000 in 50 years!

Too old
It's easy to conclude that you're too late to the party if you're, say, 60 or 70 years old. But the average U.S. life expectancy is about 81 for women and 76 for men, with more people making it into their 90s than ever. Even at 70, some of your dollars might have 20 more years to grow, or more -- if you give them a chance.

Too unknowledgeable
Sure, the more you know, the better you'll probably do in investing. But you don't have to read shelves of books and you don't need a high IQ. A simple, inexpensive broad-market index fund or two can instantly park your money in hundreds or thousands of stocks, giving you the stock market's approximate return. And there are bond funds, too. Spend a little time online and you can learn a lot.

Too busy
Busyness is a problem for many of us these days, and may explain why many people are not investing for retirement. But there are ways to set up your financial life so that investing for retirement takes up little time or energy. You could make the most of a 401(k) account at work, for example, which will automatically invest a chunk of your income into investments you choose. This offers tax advantages -- and if your employer offers matching funds, it gives you free money, too. IRAs are also simple. Set one up and send in a check every year, perhaps allocating your money to index funds.

Too risk-averse
If your aversion to losing money is what's keeping you from investing for retirement, think it through a little more. By parking money in a savings account or CD that isn't even earning enough to cover inflation (which has averaged close to 3% over long periods), your money is actually losing purchasing power over time. Being too risk-averse can put you at too much risk. Most of us need our money to grow, not shrink. And growing by 1% or 3% probably won't cut it, unless you're enjoying a fat income and hefty nest egg. Remember that index funds aside, many individual stocks are not so worrisome, and many can deliver market-beating returns, too, perhaps paying out dividends along the way.

Too in debt
Maybe you're not investing for retirement because you're deep in debt. If so, you're not alone. The 2013 EBRI survey found that 16% of workers cited debt as a major problem, and another 44% said it's a minor problem. If your debt carries a high interest rate, then that actually can be a reason to delay investing for retirement. It makes little sense, for example, to aim for unguaranteed 10% returns while paying a guaranteed 20% or more in interest. But if your debt is a 5% mortgage, you may profit more by investing extra cash in the stock market than by making additional mortgage payments.

Too many other needs
You may say you're not investing for retirement because your children require much of your money for support, or you're saving for their college educations. That's great, but don't give your financial future short shrift. Junior may be able to collect scholarships or financial aid, but your retirement is on you. Social Security will not be enough for many, if not most, folks, and few of us have pensions, or adequate ones, anymore.

Too poor
This excuse seems legitimate -- until you realize that you can be investing for retirement via contributions of just $25 or $50 per month. Dividend reinvestment plans, or "Drips," let you invest in individual stocks with modest amounts. And many brokerages and mutual funds will give you entry with small minimum requirements, too.

Too scared
Some people aren't investing for retirement because they're scared. They've seen the market plunge. Well, yes, it will do that now and then. That's why you should keep any money you'll need within five (or even 10) years out of stocks. But long-term money is likely to grow faster in the stock market than in many other alternatives.

Don't talk yourself out of investing for retirement by using faulty excuses. Jump in -- you have a lot to gain.

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