Major U.S. stock indexes were mixed as trading began in December, with many households awaiting Cyber ​​Monday deals as U.S. retailers wrapped up a huge weekend of shopping.

Meanwhile, investors will examine several economic data reports this week, culminating in the release of the November jobs report on Friday.

The S&P 500 gained 0.2% on Monday, reaching its highest close ever for the second straight day. The Nasdaq also posted a closing high, rising 1% on a strong day for the technology and communications sector. The Dow slipped 0.3%.

Shares of Super Micro Computer (SMCI) rose 28.7% to lead the S&P 500 higher on Monday. The volatile stock’s latest rise came after Supermicro said an independent audit committee found no evidence of accounting misconduct or fraud. The server maker also announced changes to strengthen its governance structure, including a new chief financial officer, a new chief compliance officer and a new general counsel.

Semiconductor equipment stocks extended gains recorded late last week after reports that proposed restrictions on exports to China could be less stringent than previously expected. Lam Research (LRCX) shares rose 6.3% on Monday, while Applied Materials (AMAT) shares gained 4.9%.

Cruise operator stocks rose after Truist analysts offered positive comments on the industry’s booking and pricing trends. Norwegian Cruise Line Holdings (NCLH) shares rose 5.4% after Truist raised its price target on the stock, suggesting the company appears to be on track to meet implied sales forecasts at its most recent investor day. Shares of Carnival (CCL) and Royal Caribbean (RCL) also rose.

Shares of Texas Pacific Land (TPL), which has significant acreage in the oil-rich Permian Basin, fell 6.1%, the biggest loss of any S&P 500 stock. The stock enjoyed a boost when it was added to the S&P 500 in late November, but has reversed those gains by December.

Shares of PG&E (PCG) fell 5% after the California-based electric utility holding company said it would raise $2.4 billion through public offerings of new common and mandatory convertible preferred stock. PG&E plans to use the proceeds from the offering for general corporate purposes, which could include funding its five-year capital investment plan.

Natural gas prices fell as forecasts for milder winter weather raised questions about key heating fuel needs. Natural gas inventories in the U.S. are reportedly at their highest level since 2016 as winter begins. The drop in prices put pressure on stocks of companies in the natural gas industry. Shares of pipeline operators Targa Resources (TRGP) and Oneok (OKE) fell 4.6% and 2.8%, respectively.