STORY: U.S. stocks closed slightly lower on Monday, with the Dow and S&P 500 slipping marginally, and the tech-heavy Nasdaq shedding six-tenths of a percent.Investors are braced for a slew of economic data this week, including the delayed release of November's nonfarm payrolls report, due out on Tuesday, and the PCE inflation report on Friday.David Steinbach is chief investment officer at Hines."I think the market today is waiting for some of the headlines with regard to the jobs data, inflation. But I think more broadly, the stock market is still pricing in a fair amount of uncertainty in terms of some questions are still unanswered and it's waiting, waiting for those answers to find full footing. [FLASH] I'm expecting in the jobs data, the numbers to be, you know, a little bit disappointing in terms of what people are hoping for in an economy running on all cylinders."In company moves, shares of Tesla rose 3.5% after CEO Elon Musk said the electric vehicle maker had advanced its robotaxi testing by removing the safety driver from the front passenger seat.Shares of ServiceNow fell 11.5% following a report the cybersecurity company is in advanced talks to buy startup Armis.And shares of iRobot plunged more than 72% after the Roomba vacuum-cleaner maker filed for bankruptcy protection.