Last Week's Biggest Movers on Wall Street

Plenty of stocks go up and down in any given week. The gainers inspire us to keep investing. The decliners keep greed in check while reminding us about the risks of the equity markets.

Let's go over some of last week's best and worst performers.

Oil-Dri (ODC) -- Up 26 percent last week

There's apparently big money to be made in selling kitty litter. Oil-Dri shareholders purred in delight after the company posted a record quarterly profit of 71 cents a share. Things aren't perfect. Sales fell slightly since a year earlier. One-time items helped deflate its effective tax rate. However, it's still an impressive showing for Oil-Dri.

TripAdvisor (TRIP) -- Up 22 percent last week

%VIRTUAL-WSSCourseInline-840%Shares of the travel reviews website operator took off after it struck a deal with Priceline (PCLN) to be a partner for its Instant Booking platform. TripAdvisor rolled out a "Buy Now" button last summer, allowing site visitors to book hotel, flight, and car rentals right from its reviews-rich listings.

Both sites will benefit from the partnership, but TripAdvisor shares were the ones that took flight on the news. Priceline's partnership validates the platform, and it will help TripAdvisor generate more commissions without having to worry about fulfillment or following through with customer service.

Pure Storage (PSTG) -- Up 13 percent last week

Some IPOs don't get hot right away. Pure Storage went public at $17 two weeks ago and investors didn't want it. The stock closed at $16.01 on its first day of trading, moving even lower the next day.

It was a different story last week. Dell's big deal to acquire EMC (EMC) lit a fire under other providers of data storage solutions. If the now privately held Dell is on a shopping spree, it may inspire its PC rivals to make big bets on other players in data storage.

BofI Holding (BOFI) -- Down 29 percent last week

Online banking is a neat way to shave overhead costs, but last week it was an online banker that was shaved down. BofI -- the parent company of Bank of Internet -- took a hit after a pair of former auditors offered up problematic assessments.

An internal auditor kicked things off by filing a complaint, alleging that BofI was hiding information from regulators. Another auditor went on to claim that he left the dot-com banker after raising similar concerns.

Spirit Airlines (SAVE) -- Down 17 percent last week

There was some choppy turbulence for Spirit investors after the bargain carrier reaffirmed its guidance, but cutthroat competition is keeping fares low through the year ahead. The ho-hum outlook led Morgan Stanley to downgrade the stock.

Spirit is a controversial name in the industry. It advertises low fares, but then slaps on a wide array of fees. Sometimes a carry-on bag will cost more than the passenger. The airline industry has been on an upswing in recent years as sector consolidation has lowered costs and increased pricing power, but that doesn't mean that everybody's a winner.

Conn's (CONN) -- Down 13 percent last week

Finally, we have a meandering consumer electronics retailer continuing to cope with deadbeat customers. In a regulatory filing, Conn's conceded that 11.9 percent of its securitized portfolio has been delinquent for more than 60 days. That's a concern, naturally, and Zacks downgraded the retailer's stock to a "strong sell" rating following the fiscal update.

Motley Fool contributor Rick Munarriz has no position in any stocks mentioned. The Motley Fool owns shares of and recommends BofI Holding, Priceline Group and TripAdvisor. The Motley Fool recommends Spirit Airlines. Try any of our Foolish newsletter services free for 30 days. Check out our free report on one great stock to buy for 2015 and beyond.