With the S&P 500 and Dow Jones Industrial Average regularly setting record highs in recent sessions, you may be tempted to dive further into equities.

But, "don't go overboard when deciding how much of your portfolio to put into stocks," advises Mark Hulbert, editor of Hulbert Financial Digest, in his Wall Street Journal column.

Since 1926, an index fund based on the S&P 500 or its predecessor would have generated a 10 percent average annual return, assuming dividends were reinvested, according to Ibbotson Associates.

Editor’s Note: Get These 4 Stocks Before 399% Stock Market Rally!

At the same time, a portfolio 60 percent weighted to the S&P 500 index fund and 40 percent weighted to intermediate-term Treasurys would have returned 8.7 percent a year.

"That certainly appears to be a rather modest price to pay for cutting your portfolio's risk nearly in half, as measured by volatility of returns," Hulbert argues.

And the premium of stock returns relative to bond returns will likely shrink in the future, he predicts. In fact, that premium already has shrunk during the last 90 years, Claude Erb, a former fixed-income manager at TCW Group, tells Hulbert.

Wade Slome, president of Sidoxia Capital, also counsels caution about jumping on the equities bandwagon.

"The risk for the 'sideliners' getting back into stocks now is straightforward," he writes in an article for Investing.com. "Sideliners have a history of being too emotional, which leads to disastrous financial decisions." They will likely buy too late and sell too early, Sloane notes.

"Rather than chase a stock market at all-time highs, the sideliners would be better served by clipping coupons, saving and/or finishing that bunker-digging project."

Editor’s Note: Get These 4 Stocks Before 399% Stock Market Rally!

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