Investors flock to cash ahead of Fed meeting

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Inside the mind of the Fed

Investors are going to the mattresses, stuffing their money away until they get better clarity on the Fed's intentions for interest rates.

Of course, the move hasn't been to actual mattresses but an intensifying push to money market funds, which have taken in $48 billion over the past four weeks and $212 billion in the second half of 2015, according to Bank of America Merrill Lynch. The $13.4 billion inflow over the past week marks the 10th-straight positive week, the longest streak since March 2008 for the $2.7 trillion money market industry.

The trend comes ahead of next week's two-day Federal Open Market Committee meeting, which likely will see the U.S. central bank approve the first increase in its key interest rate since late 2006. The Fed has kept the funds rate near zero since late-2008 after lowering it to help spur economic growth amid the Great Recession.

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While traders Friday assigned an 81 percent chance that a hike will be announced Wednesday, there's uncertainty over where rates go from there. Most on Wall Street expect the Fed to move slowly, but uneven rhetoric through the year from policymakers has inspired repeated bouts and angst that have led to volatility in the financial markets.