Many owners of Apple Inc. stock are perplexed as to why the price keeps dropping, especially in an otherwise surging equity market. Apple’s market capitalization – a measure of the overall value of a company – fell recently beneath $400 billion, its lowest mark since December 2011, and the stock is down 20 percent since Jan. 1.

Meanwhile, the S&P 500 Index has gained 8 percent. The reasons for Apple’s slide? They include disappointing fourth-quarter earnings and ongoing profit-margin pressures. The most fundamental, however, are some signs of decline in market share; that is, a rise in competition, BloombergBlack Investment Strategist Kevin Sullivan writes. Investors are rightfully worried about how companies like Samsung, Google, Microsoft and others might eat into the company’s sales. Competitors are introducing laptops, pads and smartphones that are less expensive than Apple products and according to some analysts just as good if not better.

So uncertainty is holding the stock back, Sullivan writes. This is complicated by the fact that the stock seems so undervalued (it has a forward price-to-earnings ratio of less than 10, compared to 13 for the broader technology sector) and the company in some ways seem paralyzed as to what to do with its $137 billion cash hoard.

Questions around whether the stock is in long-term freefall will probably take a couple of months to play out. In the meantime, analysts at leading brokerages are lowering their sales estimates, suggesting that there may be more near-term pain ahead, Sullivan believes.

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