10 things you need to know before the opening bell

Here is what you need to know.

Here comes the Fed. Jerome Powell is leading his first policy meeting as Federal Reserve chairman, and the central bank is widely expected to raise rates.

UK unemployment falls back near record lows. UK unemployment slipped to 4.3% between November and January, according to data released by the Office for National Statistics.

Morgan Stanley says there are 2 major reasons the stock market has already seen its 2018 peak. Based on stock index trading and sentiment shifts over the past few months, Morgan Stanley says the equity market has probably already peaked for 2018.

Facebook has shed almost $50 billion of market cap in the last 2 days. Shares of the social-media giant have fallen 9.5% so far this week following news that Cambridge Analytica accessed data from 50 million users without their permission.

Amazon is now the 2nd most valuable company in the US. Amazon finished Tuesday's trading session with a market capitalization of $768 billion, trailing only Apple ($889 billion) as the most valuable company in the US.

Salesforce is buying MuleSoft. Salesforce will buy cloud-service provider MuleSoft for $36 per share in cash and 0.0711 shares of Salesforce common stock per MuleSoft Class A and Class B common share, which amounts to $44.89 per share, or a 36% premium to Monday's closing price.

Spotify's CEO can sell a bunch of shares in the company's direct listing. Spotify CEO Daniel Ek can sell 15.8 million shares of the company, an amount worth up to $2 billion, in the company's direct listing, Reuters says, citing a filing.

A feature on Robinhood's new web platform raises questions about the strength of its user base. Robinhood, the brokerage startup known for pioneering free stock trading, claims to have 4 million registered users, but a new feature listing the most owned stocks shows Apple is the most popular stock with just 140,818 Robinhood users (3.5% of users) owning shares.

Stock markets around the world are mostly lower. Japan's Nikkei (-0.47%) lagged in Asia and Britain's FTSE (-0.48%) trails in Europe. The S&P 500 is set to open little changed near 2,719.

US economic data is light. Existing home sales will be released at 10 a.m. ET. The US 10-year yield is down 1 basis point at 2.89%.