NEW YORK (TheStreet) -- Wall Street welcomed big gains, and a 2015 winning streak, to kick off the new week. 

The S&P 500 clinched its longest winning streak this year as crude oil prices surged and boosted the energy sector. The benchmark index has gained more than 5% over the past five days after jumping nearly 2% on Monday. 

The Dow Jones Industrial Average gained 1.8% over the session, and Nasdaq climbed 1.6%.

Crude oil spiked on speculation that China will introduce more monetary stimulus measure to bolster its economy. The World Bank said on Monday it expects China to grow 7% this year but forecasts a gradual slowdown over the next two years. China's GDP has averaged 8.6% since 2010.

West Texas Intermediate crude closed 1.6% higher at $46.26 a barrel on expectations that similar actions by central banks would revitalize oil demand from the world's second-largest energy consumer. However, any further upside was limited after Saudi Arabia said it would cut the price of crude deliveries by $1.70 a barrel.

The energy sector was the best performer on markets. Exxon Mobil (XOM) , Chevron (CVX) , Kinder Morgan (KMI) , ConocoPhillips (COP) and Royal Dutch Shell (RDS.A) were all sharply higher, while the Energy Select Sector SPDR ETF (XLE) added 3%.

Biotech stocks failed to join in on the rally on Monday, though, as investors continued to flee health care after Democratic presidential candidate Hillary Clinton two weeks ago vowed to address industry "price gouging." Bristol-Myers Squibb (BMY) , Eli Lilly (LLY) , Biogen (BIIB) , and Teva Pharmaceutical (TEVA) were among the worst performers, while the iShares NASDAQ Biotechnology Index ETF (IBB) fell 0.74%.

General Electric (GE) led the Dow higher after activist investor Nelson Peltz and his hedge fund Trian Fund Management disclosed a $2.5 billion stake, the largest holding in the fund's history. Trian will hold 98.5 million GE shares. The fund has asked GE to increase cost-cutting efforts and possibly offload more of its finance assets. GE shares added 5.3%.

Twitter (TWTR) named co-founder Jack Dorsey as its permanent CEO after months of speculation. Dorsey was the frontrunner after serving as interim chief executive since former CEO Dick Costolo stepped down in July. Dorsey will step down as chairman but will remain on the board. Shares were up 7%.

American Apparel (APP) filed for Chapter 11 bankruptcy in Delaware. The teen clothing retailer had previously said in August that it had doubts it would be able to stay in business. Stores will remain open while the company seeks approval for its restructuring plans from the courts.

Google (GOOGL) officially changed its name to Alphabet on stock markets Monday. Alphabet is the parent company of Google as well as its other tech businesses. The change in corporate structure will not change the ticker symbols on the Nasdaq.

Potash Corp. (POT) was up more than 2% after it withdrew an $8.8 billion takeover offer for German-based salt producer K+S AG, which had previously rejected Potash's offer of 41 euros a share in May. Potash said that a decline in commodity markets had made the pursuit unviable.

Services growth slowed in September to 56.9 from 59 in August, according to the Institute for Supply Management. The reading came in below economists' estimates of 57.5. The report showed that the domestic economy is experiencing challenges outside of lower energy prices and the strength of the U.S. dollar.

The United States and 11 other Pacific Rim nations reached a deal on the Trans-Pacific Partnership, the largest regional trade agreement in history. The deal would unite 40% of the world's economy and lower import tariffs and other trade barriers between countries. The deal, eight years in the making, still needs to pass Congress.

More from Markets

Global Stocks Slide as Trump's New Trade War Salvo Ignites Fresh Concern

Global Stocks Slide as Trump's New Trade War Salvo Ignites Fresh Concern

Ackman Investment Buoys Lowe's; DraftKings Responds to FanDuel Merger -- ICYMI

Ackman Investment Buoys Lowe's; DraftKings Responds to FanDuel Merger -- ICYMI

Replay: Jim Cramer on the Markets, Tiffany, Micron Technology and Union Pacific

Replay: Jim Cramer on the Markets, Tiffany, Micron Technology and Union Pacific

Carnival CEO Arnold Donald: China Will Become the Largest Cruise Market

Carnival CEO Arnold Donald: China Will Become the Largest Cruise Market

Red Robin Slumps After Earnings Miss

Red Robin Slumps After Earnings Miss