“It is too early to know what policy changes will be put in place or how their economic effects will unfold,” Yellen said.

Yellen did not provide any definitive outlines on three rate hikes this year, nor did she reveal whether a rate hike might come in March or in June as most expected.

“This doesn’t mean they will move in March, but the Fed wants to have the option to move,” Omer Esiner, chief market strategist at Commonwealth Foreign Exchange, told Reuters. “The market seems to be under-pricing a upcoming rate hike.”

Even with higher rates, investors are looking to the improving economy and strengthening U.S. companies’ fundamentals to support further stock price appreciation.

“We’ll have higher rates, but if earnings can continue to move ahead, then the market will continue to grind higher,” Karyn Cavanaugh, senior market strategist at Voya Investment Management, told the Wall Street Journal.

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