The Dow Jones Industrial Average reversed course on Thursday after key inflation data was released, with Intel (INTC) plunging 10% on an earnings miss. The index ended the day down 0.2%.

As investors look ahead to the stock market opening on Friday, there are five key things to know. First, the U.S. economy grew by an annual rate of 4% in the fourth quarter of 2020, according to the latest GDP report. Second, Wall Street hit its best level in nearly 8 weeks on Thursday, with the S&P 500 and Nasdaq Composite both closing at record highs. Third, inflation data released on Thursday showed a modest increase in prices, with the Consumer Price Index rising 0.4% in December. Fourth, earnings season continues, with several major companies set to report results. Finally, there are several economic reports due out on Friday, including housing starts, industrial production, and consumer sentiment.

Overall, the stock market has been on a strong upward trend in recent weeks, with the Dow, S&P 500, and Nasdaq all hitting new highs. However, the market could be volatile on Friday, as investors digest the latest economic data and earnings reports.