US stocks retreated this week following a light calendar of economic news punctuated by a brief mid-week swoon over troubles at a leading Portuguese bank.
Equities scored modest gains Friday, partially offsetting the losses from the prior day when worries about Portugal's banking system rocked the market. But Friday's increases were not enough to offset earlier losses.
The Dow Jones Industrial Average fell 124.45 points (0.73 percent) to 16,943.81.
The broad-based S&P 500 dropped 17.87 (0.90 percent) to 1,967.57, while the tech-rich Nasdaq Composite Index gave up 70.44 (1.57 percent) at 4,415.49.
Investors pored over minutes from the US Federal Reserve's June policy meeting released Wednesday that disclosed the central bank plans to end its bond-buying stimulus program in October.
The Fed also confirmed that it will keep near-zero benchmark interest rate for "a considerable time" after the asset-purchase program ends, leaving in place the Fed's mid-2015 timeframe for raising rates. The minutes helped push stocks higher Wednesday.
But US stocks nosedived the next morning, following European markets sharply lower as investors recoiled at news Portugal's market regulator halted trading in Banco Espirito Santo (BES) amid allegations the bank's parent company covered up a 1.3 billion euro ($1.8 billion) hole in its accounts.
The news renewed concern that Portugal's banks remain vulnerable after the country emerged from a three-year international bailout in May.
Both US and European markets rose Friday following reassurances from top Portuguese officials that BES was in solid shape.
But the episode showed the brittleness of investor sentiment after a buoyant second quarter that lifted the S&P 500 4.7 percent and set several new records. Some market commentators predict a 10-12 percent correction in the weeks ahead.
"Portugal was certainly an issue," said Alan Skrainka of Cornerstone Wealth Management.
"It shows there is a lot of nervousness," after US markets hit record highs last week, he said, calling the BES news "an excuse for the stock market to sell off."
Despite a run of strong monthly Labor Department jobs reports and some other encouraging data, analysts still see signs of economic weakness. Top of the list has been disappointing news from retailers.
The Container Store pointed to a "funk" within the industry as it reported a loss in its fiscal first quarter. Gap reported that June comparable-store sales fell two percent.
-Investors 'edgy' about earnings -
The dreary retail news "tells investors that the much-anticipated economic bounce in the second quarter might be disappointing," said Christopher Low, chief economist at FTN Financial.
"People are bound to be nervous," Low added. "I expects stocks will reprice as guidance comes over the course of the next month."
Art Hogan, chief market strategist at Wunderlich Securities, described investors as "edgy" given the surge in valuations.
"We know we need further catalysts to justify the levels we're at," Hogan. "We're optimistic those catalysts will come to us during earnings season. But it's still a 'show-me' story."
On Friday, Wells Fargo kicked off earnings season for the large financials, reporting a 3.8 percent rise in second-quarter earnings to $5.7 billion, or $1.01 per share, meeting expectations.
Next week's earnings calendar picks up significantly and includes reports from most of the remaining large banks, including JPMorgan Chase and Goldman Sachs. Others to report include Johnson & Johnson, Yahoo, Intel, IBM and General Electric.
Major economic indicators include retail sales and industrial production for June and the Fed's Beige Book outlining economic conditions.
Federal Reserve Chair Janet Yellen will be back in the spotlight as delivers the central bank's semi-annual report on the economy and monetary policy to Congress in hearings Tuesday and Wednesday. Investors will be watching for clues on the direction of the economy and the outlook for raising interest rates.