US stocks pushed higher for a second week running as investor relief at higher oil prices and greater confidence over Greek debt talks and Ukraine peace prospects lifted the market.
The broad-based S&P 500 finished the week with a flourish, closing at its first record of 2015 at 2,096.99 after adding 41.52 points (2.02 percent).
The Dow Jones Industrial Average crossed its own threshold, breaching 18,000 for the first time this year to end at 18,019.35, up 195.06 (1.09 percent). The tech-rich Nasdaq Composite Index gained 149.44 (3.15 percent) at 4,893.84.
"While investors recognize the market may be expensive, I don't think too many people are calling for the next crisis around the corner," said Jack Ablin, chief investment officer at BMO Private Bank.
The gains came despite some disappointing US data, especially a January retail sales report that showed a drop of 0.8 percent compared with the prior month.
That dulled some of the luster from last week's surprisingly robust US jobs report. Yet, investors largely shrugged off the data, focusing instead on the pickup in the oil market, with US prices finishing above $50 a barrel for the second week in a row.
Investors took an optimistic view of a cease-fire roadmap unveiled Thursday between Kiev and pro-Russian rebels. Ukraine officials continued to speak cautiously of the deal as fighting raged on Friday.
They also saw reason to be optimistic about ongoing talks between Greece and the eurozone over Athens's demand for a new bailout deal, taking cues from European markets, which rose Friday in part due to expectations that an agreement will be reached to avoid a Greek sovereign debt default.
Ablin said investors still do not know what to expect from Greece, but have become less rattled by a potential Greek departure from the currency bloc.
"Investors increasingly believe that if Greece were to leave the eurozone, it wouldn't be the end of the world," he said. "In fact, it could catalyze growth."
- Apple soars, AmEx sinks -
Among corporate news stories, Apple stole more headlines when it became the first public company to reach a market value of $700 billion. The jump followed an upbeat appraisal of the company's iPhone and soon-to-arrive smartwatch prospects by chief executive Tim Cook at a technology conference.
The technology giant rose 6.9 percent for the week, ending with a market capitalization above $740 billion.
The week's most dramatic merger was US online travel operator Expedia's announcement that it will buy rival Orbitz Worldwide for about $1.6 billion. The deal is the latest move to consolidate the online travel industry and comes less than a month after Expedia announced the purchase of rival Travelocity in a $280 million deal.
Dow component American Express took a hit when it announced that its venture to provide exclusive credit cards at Costco Wholesale stores would end in March 2016. American Express sought to extend the venture, but said it was "unable to reach terms that would have made economic sense for our Company and shareholders." Shares fell 8.2 percent for the week.
Shareholder activists continued to pressure big companies, with Nelson Peltz's firm Trian Fund Management amplifying its call for the election of four activist-backed board members at DuPont and Harry Wilson, a corporate reorganization specialist who worked on the Obama administration's auto task force, publicly calling for General Motors to buy back at least $8 billion in shares.
Next week's earnings calendar includes Wal-Mart Stores, one of the first big retailers to report results for the critical holiday-shopping period.
The calendar also includes data on the housing market, inflation and industrial production and the release of minutes from the Federal Reserve's January monetary policy meeting.