However, the California State Teacher's Retirement System—known as CalSTERS—is actually shedding some of its U.S. stocks, the pension fund's chief investment officer said.
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Christopher Ailmann said a three-month chart of the S&P 500 shows that the market is in a "topping phase." Therefore, the fund has been shaving off profits and believes there are unique opportunities in Europe and Japan, if the currency is hedged.
"You've had a six-year bull market, which is very long in the tooth," Allman said in an interview with "Closing Bell."
"I would encourage everybody to look at their 401(k) statements and rebalance that asset allocation. You just can't keep riding stocks."
Many investors are eyeing the Fed and trying to determine when it will begin to raise rates.
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For Heider, when that happens, it's another buying opportunity.
"The reality is, I think when the Fed does raise rates you'll see increased volatility, representing an opportunity to buy into the equity market," Heider said.
While some believe the central bank could begin tightening this summer or September, Sterne Agee chief economist Lindsey Piegza thinks it won't happen until 2016.
She believes Fed Chair Janet Yellen wants to make sure the economy is strong enough so that there is not an adverse reaction from the marketplace.
"That means the Fed is likely to err on the side of caution, waiting for confirmed and prolonged strength before beginning to raise rates," Piegza said.