Stock ticker showing a range of price changes.

Image source: Getty Images.

Stocks hardly moved on Thursday, with both the Dow Jones Industrial Average (^DJI -1.19%) and the S&P 500 (^GSPC -0.73%) indexes finishing less than 0.1% off their opening values.

Today's stock market:

Index

Percentage Change

Point Change

Dow

(0.03%)

(5.96)

S&P 500

0.06%

1.30

Data source: Yahoo! Finance.

Financial stocks were among the biggest daily losers, which pushed the popular Financial Sector SPDR Select ETF (XLF -0.72%) down 0.4%. On the other hand, gold prices hit a two-month high and that generated a 6% spike in the leveraged bullish bet on the precious metal ETF, Direxion Daily Gold Miners Bull 3X (NUGT 5.38%).

As for individual stocks, both Facebook (META -10.96%) and Costco (COST 0.14%) attracted heavy investor interest following important operating news.

Facebook keeps winning

Facebook shares wiggled between a slight gain and loss as investors digested its fourth-quarter earnings report. Sales improved by 53%, marking a slowdown from the 59% spike in the prior quarter. Yet audience and engagement metrics remained robust, with daily average users up 18% and monthly users up 18%, or 269 million, to 1.86 billion. Facebook squeezed plenty of extra money from those people, too. Average revenue per user spiked to $19.81 in the U.S. -- up 45% over the prior year. "This was another good quarter and a good end to 2016," CEO Mark Zuckerberg said in a conference call with investors.

Chart showing average revenue per user rising in each region around the world.

Image source: Facebook investor presentation.

Investors can't count on that level of blowout financial and operating wins continuing for long. In fact, Facebook again warned that its advertising growth pace will come down meaningfully over the next few quarters as it levels off on the volume of ads that it shows in user feeds. In addition, executives see 2017 as a heavy investment year, with spending on hiring, research and development, content, and sales and marketing all slated to rise.

Taken together, it's unlikely this year will be a repeat of last year's 57% revenue spike and near tripling of net income to over $10 billion. Yet, Facebook has no shortage of long-term growth opportunities, beginning with video, which Zuckerberg said he sees as a massive trend comparable to mobile. That's saying a lot, considering that mobile now accounts for 84% of ad revenue -- up from 69% just three years ago.

Costco gets more crowded

Costco shares spiked by 4% to nearly set a new high after the company reported healthy sales results for the month of January. Comparable-store sales rose 6% in the key U.S. market, which doubled the prior month's result. After accounting for fuel price swings and foreign exchange rate changes, overall comps rose 5% last month, for a nice acceleration from December's 3% increase.

Woman shopping in a warehouse store.

Image source: Getty Images.

Investors are even more focused on comps growth lately since the warehouse retailer just closed its slowest fiscal year of gains since 2011. Customer traffic, membership growth, and renewal trends all ticked lower last year. Yet a big part of that decline can be pinned on the disruption caused by Costco's shift to a new co-branded credit card.

January's sales spike suggests that the company could be returning to its market-thumping ways. That would be bad news for competitors, and it might also spell surging profits ahead since executives will feel much better about raising membership fees once customer traffic and renewal trends are improving again.