Stocks in the first half of 2015 offer a very mixed bag

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Pisani: Sectors on upside

The market action has been very uneven in the first half of the year. The is only 3 percent from its May historic high, but that is a deceptive picture.

There have been some notable sector winners, but there are also many—perhaps most—that still have modest gains for the year, but have stalled out in the second quarter. And then there is a distinct group that is in a clear downtrend.

If there was ever an argument for owning a broad portfolio of stocks, the first half of 2015 should be Exhibit 1.

First, let's look at the winners on an uptrend so far this year:

Banks have benefited from a rising interest rate environment and hopes for an improving economy, while health care, particularly biotech but also pharmaceuticals, have also been strong. The boost to HMOs and hospitals from the Supreme Court ruling on Obamacare has also bolstered the overall sector.

But there are many sectors that started the year strong, and have begun to stall in the second quarter. Two examples:

The housing numbers have shown notable improvement, as have earnings of companies like Lennar, but there is still an affordability issue hanging over the home building industry. Prices are high and getting higher, wages are still stagnant when inflation-adjusted, and the specter of higher mortgage rates have investors cautious.

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