On Wednesday, US technology stocks rose to a record high on the back of strong corporate profits, while shares of small companies led declines, and Treasuries gained on an uptick in growth concerns.

Google parent Alphabet Inc., Amazon.com Inc., and Tesla Inc. lifted the tech-heavy Nasdaq 100 for the third day of rallying gains. The S&P 500 and Dow Jones Industrial Average indices fell after setting closing records Tuesday. However, McDonald's Corp and Coca-Cola Co both rose following positive results. Microsoft Corp also gained momentum after bullish reports late Tuesday night.

"Tesla's rally is making the S&P 500 even more of a concentrated bet on disruptive technology. Tesla is now solidly in 'must watch' territory along with the rest of US Big Tech for its potential impact on day-to-day moves in the S&P 500," Nicholas Colas, co-founder of DataTrek, said.

Longer bonds continued to outperform US shorter-dated debt ahead of the government's auctions of five-year notes on Wednesday and the seven-year sale on Thursday.

Investors are relying on earnings to support equity prices, and so far the reporting season has been solid. However, concerns remain that over time rising raw material and wage costs, as well as supply chain problems, could crimp margins and affect the global economic recovery.

"Equities moved higher last week, fully recovering from the September dip. That said, in our view, last week's positive performance does not create headwinds for the performance ahead," Lauren Goodwin, economist and portfolio strategist at New York Life Investments, said. "Market positioning is still approximately neutral, which could point to further upside potential in equity markets. We believe recent positive market moves could be the beginning of a now-earlier 'Santa Clause rally.'"

Here are some events to watch this week:

• Bank of Japan monetary policy decision, briefing, Thursday
• ECB rates decision, President Christine Lagarde briefing, Thursday
• US GDP, initial jobless claims, Thursday
• G-20 joint finance and health ministers meeting ahead of the weekend leaders' summit, Friday