But if you were contributing regularly all that time—say, $1,000 a month—your loss on March 9, 2009, would have been about a third less than the Dow's, and you would have recovered your losses by January 2011—more than two years before the Dow itself did.
What's wrong with the other choices available in your plan? Some, including bonds, cash and other types of assets, might be appropriate later, when you're ready to diversify the money you've accumulated, but stock funds deliver the best returns for your new contributions.
Instead of trying to choose which individual stock funds will perform best, invest in as many stocks as possible that vary by style (growth and value), cap (large, medium and small), sector (type of industry or geographical location) and so on.
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You'll invest in all of these through mutual funds or—preferably, if you can—exchange-traded funds, which offer many advantages, including much lower cost.
If, instead of a 401(k), your employer offers another type of retirement plan—such as a 401(b) or 457—stock funds are still your best option. Fixed annuities usually provide low returns. Variable annuities are just mutual funds wrapped in insurance, making them far costlier, unless your company offers groups of annuities, which can be lower in cost.