Defensive stocks outperformed cyclical stocks for the first half of the year, but that pattern is now likely to reverse, Justin Lahart writes in The Wall Street Journal's Heard on the Street column.

To see the pattern, he says, look at the period From Jan. 1 until the Standard & Poor's 500 Index peaked on May 21 — the day before Federal Reserve Chairman Ben Bernanke indicated the Fed might taper its quantitative easing (QE) soon.

A market-weighted index of S&P 500 defensive sectors, including consumer staples, healthcare, telecommunications services, utility and real estate investment trusts soared 19.2 percent during this period. That bested the 16.4 percent gain for cyclicals.

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Since May 22 through last Thursday, defensive shares have fallen more than cyclicals — 3.9 percent versus 3 percent, respectively.

But by one measure, defensive stock prices still carry a 1.57 percentage point premium over cyclicals, compared with a historical average of 0.36 percentage point, according to Credit Suisse.

That's unlikely to continue, Lahart writes.

"The two things that have propped up defensive stocks — worries about economic growth and ultra-low long-term interest rates — are getting kicked away, setting up a rotation into more cyclical stocks," he says.

"It is time to play offense."

Chris Baggini, senior portfolio manager at Turner Investments, tells USA Today now "is a good time to be investing in the stock market." He too sees economic growth increasing and thus prefers cyclicals over defensive stocks.

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