5 things to know before the stock market opens Monday

• The S&P, Dow and Nasdaq all hit 52-week highs on Friday, and inflation data this week will help to chart the Federal Reserve's path ahead.
• Berkshire Hathaway's operating earnings jumped 28% year over year, and Warren Buffett said there's only so much more his conglomerate can do with its growing cash pile.
• The billionaire-backed Koch network is pulling its financial support for Nikki Haley after Donald Trump defeated her in her home-state South Carolina presidential primary.

Here are the most important news items that investors need to start their trading day:

The week ahead will tell whether the Federal Reserve can damper investor enthusiasm. A rally fueled in large part by blowout Nvidia earnings pushed the S&P 500, Dow Jones Industrial Average and Nasdaq all to 52-week highs on Friday. Stocks surged to end the week even as more Fed policymakers indicated they will move slowly to cut interest rates, as inflation eases but remains more stubborn than the central bank would have hoped. The Fed's preferred inflation measure, the personal consumption expenditures price index, is due Thursday and will help to determine the path of policy ahead. Earnings from companies including Lowe's, Macy's, TJX, Salesforce, Paramount and Best Buy will also offer a read into the health of the economy. Follow live market updates here.

Berkshire Hathaway's business keeps booming. Warren Buffett's conglomerate reported Saturday that operating earnings at its insurance, railroad and utilities businesses jumped 28% in the fourth quarter to $8.48 billion. It held $167.6 billion in cash at the end of the period, a more than $10 billion increase from the prior quarter. Buffett on Saturday cautioned there are only so many more things Berkshire