Costco (Nasdaq: COST) is expected to report Q4 earnings on Oct. 10. Here's what Wall Street wants to see:

The 10-second takeaway
 Comparing the upcoming quarter to the prior-year quarter, average analyst estimates predict Costco's revenues will increase 12.8% and EPS will expand 21.3%.

The average estimate for revenue is $31.78 billion. On the bottom line, the average EPS estimate is $1.31.

Revenue details
 Last quarter, Costco notched revenue of $22.32 billion. GAAP reported sales were 8.2% higher than the prior-year quarter's $20.62 billion.

Source: S&P Capital IQ. Quarterly periods. Dollar amounts in millions. Non-GAAP figures may vary to maintain comparability with estimates.

EPS details
 Last quarter, EPS came in at $0.88. GAAP EPS of $0.88 for Q3 were 21% higher than the prior-year quarter's $0.73 per share.

Source: S&P Capital IQ. Quarterly periods. Non-GAAP figures may vary to maintain comparability with estimates.

Recent performance
 For the preceding quarter, gross margin was 12.5%, 10 basis points better than the prior-year quarter. Operating margin was 2.8%, 10 basis points better than the prior-year quarter. Net margin was 1.7%, 10 basis points better than the prior-year quarter.

Looking ahead

The full year's average estimate for revenue is $98.75 billion. The average EPS estimate is $3.86.

Investor sentiment
 The stock has a five-star rating (out of five) at Motley Fool CAPS, with 4,370 members out of 4,524 rating the stock outperform, and 154 members rating it underperform. Among 1,232 CAPS All-Star picks (recommendations by the highest-ranked CAPS members), 1,209 give Costco a green thumbs-up, and 23 give it a red thumbs-down.

Of Wall Street recommendations tracked by S&P Capital IQ, the average opinion on Costco is outperform, with an average price target of $86.19.

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