If you're an Apple (NASDAQ:AAPL) investor used to obsessing over the company's newest products or market share in key categories such as smartphones and tablets, the new area of focus around the company have taken a turn to the deep corners of finance: Apple's gross margin is now the most closely followed area for investors.

The problem is that rising sales combined with decreasing margins can sap earnings growth for companies even as their products continue gaining momentum. As an example, between 2005 and 2008, Dell (UNKNOWN:UNKNOWN) rode rising PC sales to a 24% boost in sales, yet pricing pressures led to declining profits over that time.

The largest fear for Apple investors has turned to whether the company will keep growing sales across the coming year, while they see its profits decline from the year before as margins sit well below where the were in the previous year. As tech analyst Eric Bleeker notes in the following video, the unique qualities of being Apple means the company won't compromise on the build quality of its devices. As smartphone competition heats up and Apple looks for ways to stay ahead of the competition, that probably means Apple won't again achieve its peak gross margins of 47.4% from last March.

That's not to say Apple can't grow profits again, especially as it hits "easier" gross margin comparisons later this year, but it does mean if you're an Apple investor, you'll need to shift your analysis to include gross margins as you're watching their results across the coming year. To see Eric's full thoughts, watch the video.

Eric Bleeker, CFA, has no position in any stocks mentioned. The Motley Fool recommends and owns shares of Apple. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.