Amazon (AMZN - Get Report) reports earnings Thursday and one of the keys investors will be watching is around a potentially negative data point.

Analysts are looking for adjusted earnings per share of $7.38 on revenue of $68.817 billion. Since September 5, the stock has fallen as much as 7.3%, but is now down only 4.5%. That's for several reasons, which include broader market sell-offs, but one of the reasons for the pressure on the stock is because of the most important point investors will watch on the earnings.

That'll be margins.

Margins

Gross margin is expected to shrink year-over-year as Amazon aggressively invests in one-day delivery, which will include heavy initial shipping, fulfillment and logistics costs for the next year or two. This will flow through to lower operating margins.

And there is "potential that stepped-up one day investments may have a greater than expected impact on operating margin," RBC Capital Markets analyst Mark Mahaney wrote in a note out Sunday evening.

For the year, Amazon is expected to see an operating margin of around 5.2%, against last year's 5.3%. Several analysts in the past month-and-a-half have begun to model what the lower near-term margins will look like, saying that they could be hit materially, but should regain in the medium to longer-term. This could lower Amazon's earnings dollar figure as well.

More E-commerce Growth

Sure, some Amazon bulls have recently pointed out that e-commerce growth in the U.S. is still looking stronger than many think, even though it's decelerating.

But it's international adoption that Amazon wants to capture. Mahaney's recent in-depth research on Amazon's global e-commerce opportunities shows a potential $25 billion revenue opportunity in aggregate in India, Brazil, Turkey, Mexico and Australia. These results won't show up in any meaningful way on this earnings report, but management will likely shed some light on the viability and timing of those plans on the earnings call.

Mahaney, a bull on Amazon, with a $2,600 price target, is looking for international e-commerce revenue growth of 22% to $18.7 billion for the quarter. He models a loss on that segment of $1.1 billion, as that expansion is still in its early stages.

AWS

Wall Street is looking for Amazon Web Services revenue of $9.11 billion.

Amazon is currently a market leader in cloud, with a seemingly ever-growing segment that has been a savior for the stock. But Wedbush Securities analyst Dan Ives sees arch rival Microsoft (MSFT - Get Report) catching up.

Look for clues on the earnings and the call that Amazon is maintaining or losing market share in its highest growth and higher margin segment.

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