What a difference a month makes. Especially when it was last month.

In mid-December, Charles Schwab (SCHW) chief investment strategist Liz Ann Sonders told Yahoo Finance Editor-in-Chief Aaron Task that she was optimistic the bull market would continue in 2015. She said the market reminded her of the late 1990s — in a good way.But in her most recent note, Sonders writes, “I have not become a market bear; but I am much more cautious than at any point in the past few years.”

January was a month of volatility in the markets. For the first month of the year, the Dow (^DJI) was down 3.7% and the S&P 500 (^GSPC) fell 3.1%. The Nasdaq (^IXIC) shed 2.1%.

Speaking with Task again on Wednesday, Sonders explains her slight change of heart. “We came into 2015, and even prior to that when I wrote my 2015 outlook that it was likely to be a more volatile year,” she says. “I think some of what happened more recently reinforces that, and gives me a little more angst that we might see a greater frequency of or a more significant pull back than what we’ve gotten used to in the last couple of years.”

“But I don’t have any fear that what we’re seeing here is the end of the bull market,” she says

Sonders’ comparison to the late 1990s is worth noting though. “You had a near cyclical bear market in 1998, but it was in the context of a secular bull market that still had a couple of years to go,” Sonders says. “And I think we are still in that environment.”

An old adage on Wall Street points to January as setting the tone for the rest of the year in terms of stocks. So last month’s volatility doesn’t bode well.  However, last year bucked that notion; after a dismal January the S&P 500 ended 2014 with a gain of more than 11%.

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Despite growing headwinds domestically and abroad, U.S. stocks have outperformed their counterparts handily over the past few years. But that may be changing. “I think this will be the first year in quite sometime where global diversification and more tactically oriented asset allocation is going to pay dividends,” Sonders says. “A lot of investors in the last couple of years have looked at the out performance of the U.S. market and just said why bother?”

Sonders’ recommendation (and that of Schwab as well) is neutral on U.S. stocks, while their recommendation on emerging markets is overweight.

Still investor sentiment remains positive.  “What was pervasive in the last several years is how quickly pessimism would come back with even a slight 2 or 3 percent decline in the market,” Sonders says, “So you almost reverted to panic very, very quickly.”

Sonders says this market has a different “flavor” because sentiment remains in tact for the most part. Even though the market hasn’t pulled back too dramatically she says, sentiment has “really hung in there.”

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