Last week, investors got a peak at how well retailers are faring after companies from Wal-Mart Stores ( WMT | Quote | Chart | News | PowerRating) to Wet Seal ( WTSLA | Quote | Chart | News | PowerRating) reported their sales results for April. For the most part, April retail sales were better-than-expected, showing signs that their declines are slowing. This week, earnings from Wal-Mart, Macy's ( M | Quote | Chart | News | PowerRating), Kohl's ( KSS | Quote | Chart | News | PowerRating) and Nordstrom  ( JWN | Quote | Chart | News | PowerRating) will give investors a better idea of their outlooks for the near future.

Priceline.com ( PCLN | Quote | Chart | News | PowerRating) is due with its first-quarter results in the extended-hours session Monday. The average analyst estimate in the Thomson Reuters survey is for $0.91 per share, up from $0.76 per share a year ago, on revenue of $440.8 million.

Investors going long should know that Priceline.com shows a tendency to widen its next day share movement following an evening earnings release, doing so for 15 of the past 21 quarters. In the near-term, the stock is also showing that pattern, widening its share move three times in the most recent four quarters. On February 18, the stock rallied 12.8% in after-hours trading and extended those gains the following regular session, ending up 16.6%.

Looking deeper into the performance data, longs may be interested to know that Priceline has seen a positive post-bell earnings-driven trade in 13 of the 21 quarters we've tracked, and in 10 of those upside evening moves the stock has followed that trade with a more aggressive positive run in the next day's regular session.

Whole Foods Market ( WFMI | Quote | Chart | News | PowerRating) is another stock that likes to widen its extended-hours move following earnings. On Wednesday, the high-end grocery chain is expected to report earnings of $0.18 per share, down from $0.29 a year ago, on revenue of $1.87 billion.

Whole Foods has developed a strong pattern of widening price moves between the sessions following its after-hours earnings-related events, extending its move after 14 of its past 19 earnings-related events. In the near-term, the pattern is mixed, however, with two narrowing and two widening events in the last four quarters. On February 18, the stock rallied 7.3% in after-hours trading after quarterly results beat the Street. The stock extended those gains the following regular session, ending up a whopping 37.2%.

Cassie Slane is a Senior Editor at www.MidnightTrader.com.