CNBC.com's MacKenzie Sigalos brings you the day's top business news headlines. On today's show, Bob Pisani explains the new ETF that tracks social media hype. Plus, Alex Sherman breaks down his reporting about Amazon's push to exclusively air Thursday night NFL games.

Dow falls more than 300 points as Powell fails to ease rate fears, Nasdaq goes negative on the year

U.S. stocks fell sharply on Thursday after Federal Reserve Chair Jerome Powell failed to reassure investors that the central bank would keep surging bond yields and inflation expectations in check.

The S&P 500 closed the wild session down 1.3% to 3,768.47 after dropping 2.5% at its session low. The Dow Jones Industrial Average slid 345.95 points, or 1.1%, to 30,924.14. At one point, the blue-chip benchmark tumbled more than 700 points. The Nasdaq Composite fell 2.1% to 12,723.47 as growth stocks led the declines amid rising rates. Tesla shares dropped nearly 5%.

With Thursday's steep sell-off, the Nasdaq turned negative on the year with a 1.3% loss. The tech-heavy benchmark also fell into correction territory on an intraday basis, down more than 10% from its recent 52-week high.

'Buzz' ETF tracking social media sentiment launches Thursday amid Reddit manias in stocks

Is it time for an ETF that measures hype?

Measuring the buzz around stocks mentioned in social media is all the rage. Now, there's an exchange-traded fund for that.

The Van Eck Vectors Social Sentiment ETF (BUZZ) selects 75 stocks with the most bullish social media sentiment and packages them into an ETF.

This is essentially a momentum index, but instead of tracking stocks that are moving on price, BUZZ tracks stocks that are getting a lot of social media hype.

Amazon wants to be the exclusive provider of all Thursday NFL games starting in 2023

Amazon wants to be the National Football League's exclusive producer of Thursday games starting in 2023, but the NFL may decide to keep certain games on the NFL Network and take less money from Amazon, according to people familiar with the matter.

Amazon is in talks with the league to pay about $1 billion for an entire season's worth of exclusive games, outside of the local TV markets of the two teams playing, said the people, who asked not to be named because the talks are private. The talks are ongoing and no decision has been made, said the people.

In a new agreement, Amazon would be responsible for all the production costs and would still need to pay a local broadcaster to produce the game for home markets, as the NFL wants the Thursday night games to be broadcast on local TV in each of the participating teams' home markets.