What happened

Shares of Amazon.com (NASDAQ:AMZN) increased 13.2% in August, according to data from S&P Global Market Intelligence. This brings the e-commerce and cloud-computing behemoth stock's year-to-date 2018 rise to 72.1% through Friday, Aug. 31.

For some context, the S&P 500 returned 3.3% last month and has returned 9.9% so far this year.

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Image source: Getty Images.

So what

We can attribute Amazon's robust August performance to a continuation of the strong momentum the stock has had all year and the company's release of powerful second-quarter earnings on July 26.

For the quarter, Amazon's revenue jumped 39% year over year to $52.9 billion. Net income increased more than 12 times to $2.5 billion; on a per-share basis, results soared 1,168% to $5.07. The bottom-line demolished Wall Street's consensus of $2.50 per share.

Revenue growth was strong across all three segments, rising 44% in North America, 27% in international, and 49% in Amazon Web Services (AWS). The North America business got a boost from the company's acquisition of Whole Foods in the third quarter of last year. North America and AWS posted robust profit growth, with North America's operating income soaring 321% to $1.8 billion and AWS's climbing 79% to $1.6 billion. International's operating loss narrowed 32% to $494 million. Overall operating income went up 378% to $3.0 billion.

Now what

More fantastic growth appears to be on the horizon. For Q3, Amazon guided for revenue of $54.0 billion to $57.5 billion, representing growth of 23% to 31% year over year. It expects operating income of $1.4 billion to $2.4 billion, representing growth of 303% to 592%.