The end of the Federal Reserve's mammoth stimulus may mean the end of the stock market rally — or worse, one expert warns.

The start of the Fed's much-anticipated taper and market's lackluster start for 2014 doesn't have investors concerned — yet.

But they should worry, writes Thomas H. Kee Jr., president and CEO of Stock Traders Daily, in an article for MarketWatch.

Editor’s Note: 38 Trades That Could Turn $1,000 Into $49,000

The Fed's $1.2 trillion capital infusion was a major reason for last year's huge the stock market gain. That stimulus will likely disappear this year. The central bank has already said it will cut its monthly $85 billion bond purchases by $10 billion.

Since the growth rate is tied to the rate of available investment dollars, growth declines with a drop of investment dollars, Kee says.

"More importantly," he says, "the natural rate of change in the net new money available to be invested into the U.S. economy is already declining aggressively, according to my proprietary macroeconomic work, but that natural weakness has thus far been completely offset by the constant infusions of the FOMC" (Federal Open Market Committee).

When the Fed stimulus goes away, he predicts, the change in investment dollars available and economic growth will revert to a more natural rate.

"It may even experience a period of withdrawal if the stimulus exodus happens too fast," he cautions. "Either way, complacent investors should absolutely be less sanguine, and if liquidity levels are important, prudent investors should actually become concerned."

Look for a stock market downturn as the Fed taper continues over the coming months, he says, predicting the market will "react adversely."

He says the market's inability to rebound after the Fed's first cut in its stimulus is a red flag.

"I know most investors are not concerned at all, even those who are only recently back above water from 2007, but my analysis tells me another major drawdown can come, and investors should be attentive to the material changes that are happening in front of our eyes."

Some experts see the market's weak start in 2014 as a warning sign. The S&P 500 dropped 0.6 percent in the first five days of the year.

"When the year starts out crappy," said Stock Trader's Almanac Editor Jeffery Hirsch, reports USA Today, "it puts a damper on people's outlook."

How stocks perform in January can foreshadow the entire year, he said.

Editor’s Note: 38 Trades That Could Turn $1,000 Into $49,000

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