What you need to know on Wall Street today

Welcome to Finance Insider, Business Insider's summary of the top stories of the past 24 hours.

Senate Republican leadership released the updated version of its healthcare bill on Thursday, but continued pushback from its own conference likely puts the legislation in the same perilous position as previous iterations. Here's what you need to know:

• Republicans just released a new healthcare bill - here are all the changes
• "Everything is in jeopardy" for children who count on Medicaid, and that's turning their parents into activists
• From acne to pregnancy, here's every "preexisting condition" that could put your insurance at risk under the Senate's healthcare bill
• The new Senate healthcare bill contains a big sweetener for one particularly important senator
• One chart blows up Trump's promise that his budget will eliminate the deficit
• The White House made a video attacking the budget office that gave devastating reviews to the GOP healthcare bills

In markets news, the equity chief at $5.4 trillion investment juggernaut BlackRock thinks you should shrug off one of the market's biggest fears. The giant fund manager also has a plan to become "ubiquitous in every securities market." And a "new phenomenon" is helping propel stocks to record highs.

Janet Yellen went to Congress and got grilled about the Fed's leaks and secret speeches. And the Trump administration branded its economic plan "MAGAnomics."

In Wall Street news, Goldman Sachs is changing its dress code to appeal to engineers used to a casual startup environment. Investors have reportedly yanked $400 million from David Einhorn's hedge fund.

Qatar Airways is going through with its plans to buy a stake in American Airlines. Delta's profit tumbled.

Britain's financial regulator is paving the way to bring Saudi Aramco's IPO - the biggest in history - to London. US shale firms are teaming up with Wall Street to frustrate OPEC. And Big Tobacco has been waging a secret campaign to undermine a global anti-smoking pact.

In tech:

• MORGAN STANLEY: Microsoft's huge growth has nothing to do with its fight against Apple
• UBS: Wall Street might be underestimating the most important part of Netflix's business
• STIFEL: Buy Snap because it's what investors want Twitter to be
• GOLDMAN SACHS: There's a fortune to be made analyzing sports stats

Lastly, a massive blackout hit New York City 40 years ago today - here's what it looked like.