Rise and shine, bargain-hunting shoppers. Discount warehouse king Costco (NASDAQ:COST) plans to open its doors (or at least its books) for you bright and early on Thursday. Although the company hasn't set a specific time for its fiscal Q1 2006 earnings release just yet, this is historically a "before market open" kind of company, and its 11 a.m. scheduled conference call suggests that will hold true tomorrow as well.

As for what the morning holds, analysts are feeling cautiously optimistic. They expect Costco to post roughly an 11% rise in sales and to transform that into a 12% increase in profits per share (to $0.45). In one respect, that kind of performance would best the results reported a few weeks back by competitor BJ's (NYSE:BJ), which announced a 9% revenue increase in its own fiscal third quarter. From another perspective, however, Costco will have to outperform analysts' expectations to match its rival; growing profits apace with sales might be good most days, but BJ's grew its own profits twice as fast as sales (19% year over year).

On the other hand, at least analysts believe Costco outperformed its larger rival, Wal-Mart (NYSE:WMT), which just finished reporting 10% sales growth and 6% profit growth.

Relative performance aside, though, what should Foolish investors expect from Costco?

In a word: cash. In the three and a half years since we picked Costco to join the stable of market-beating stocks at our Motley Fool Stock Advisor newsletter, Costco has, well, beat the market. It's returned 31% since we picked it, versus a market gain of 14%. However, the company's performance over the past year has been somewhat underwhelming, at least in this Fool's view. In fiscal 2004, Costco generate a whopping $1.4 billion in free cash flow, as opposed to just $900 million in reported profits under GAAP -- wonderful news. But last year, that relationship reversed itself; Costco generated just $800 million in free cash flow but reported earning $1.1 billion in profits.

That's not a trend we'd like to see repeated this year. Although Costco doesn't usually provide cash flow statements along with its earnings releases, keep a close eye out for its SEC Form 10-Q filing, which usually comes out about three weeks after the earnings release. Once you see it, check out the cash flow statement it will contain, and assure yourself that Costco's cash is flowing strongly again. Otherwise, this company's status as a market-beater might be the next thing to get discounted.

Costco is an official recommendation of the Motley Fool Stock Advisor newsletter, where we monitor all our recommendations, updating you on major developments through articles on Fool.com, and in mid-month and semi-annual reviews in our newsletter. Take a free trial right now for access our entire archives -- no extra charge.

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Fool contributor Rich Smith has no position in any company named above.